Keywords

1 Behavioral Restraint: Fighting the Urge

Effective functioning sometimes requires behavioral restraint , that is, resistance against an urge to act in a way that could yield an undesired consequence or set of consequences. Consider, for example, an alcoholic experiencing an urge to drink or a soldier experiencing an urge to flee. Processes involved in behavioral restraint commonly are referred to as self-regulatory or inhibitory control processes. They are thought to be multifaceted and to engage multiple bodily systems, including the cognitive, affective, and behavioral systems (Baumeister 1998; Molden et al. 2012).

2 Restraint Intensity

In this chapter, we examine restraint from the perspective of an integrative analysis that has guided research in our laboratory for over two decades. The analysis offers an understanding of restraint intensity—that is, the degree of restraint at a point in time —and makes suggestions about cardiovascular (CV) responses that might be associated with it. An understanding of restraint intensity is important in part because restraint outcomes—i.e., self-regulatory successes and failures—should at least sometimes depend on it (Harkins 2006). An understanding also is important because there is reason to believe that restraint could sometimes impact health. Thus, for example, Pennebaker and colleagues (Pennebaker 1989, 1995; Pennebaker et al. 1988) have argued that personal trauma can produce urges to disclose and that resistance against these can yield adverse health consequences, including hypertension and compromised immune system function (see also Polivy 1998). A common assumption is that health risk increases the more frequently and forcefully people resist, which highlights the need for a conceptual framework that allows anticipation of the presence and power of resistance.

Suggestions about CV responses that might be associated with restraint intensity are noteworthy because they draw attention to pathological pathways through which restraint could lead to some adverse health outcomes (Bongard et al. 2012; Contrada 2011; Kamarck et al. 1997). The suggestions also present the possibility that the CV system could provide a covert means of assessing degrees of resistance, something that could be of practical value in laboratory, clinical, and other settings.

3 Integrative Analysis

The integrative analysis begins with the idea that a particular class of CV adjustments—those associated with beta-adrenergic sympathetic nervous system (SNS) activity—vary with effort, that is, the degree to which people work intensively in a performance situation (Kahneman 1973; Higgins 2006). The greater the level of effort, the more pronounced the adjustments are expected to be. This is a simple adaptation of the well-known “active coping” hypothesis proffered by Obrist (1976, 1981; Light 1981).

Beta-adrenergic activation increases the frequency and force of ventricular (heart) contractions (Brownley et al. 2000; Kelsey 2012). However, frequency effects can be masked by coincidental parasympathetic nervous system activity, which works to slow heart rate. Accordingly, heart contraction force is considered to be the preferred, “gold standard” beta-adrenergic index.

A secondary “downstream” indicator of beta activation is systolic blood pressure (SBP), defined as the peak arterial pressure following a heartbeat. SBP is determined by the force of its preceding beat in combination with vascular resistance—vascular constriction affecting space in the vascular network. Holding constant or increasing vascular resistance (i.e., holding constant or decreasing vascular space), SBP should rise with heart contraction force and, thus, beta-adrenergic activation. SBP could rise with contraction force in the presence of a decrease in vascular resistance (i.e., an increase in vascular space), although this would depend on the balance—or relative strength—of the relevant changes in force and resistance. Thus, for example, a sharp increase in contraction force might cause SBP to rise in the presence of a modest resistance decrease, whereas a blunted increase in contraction force might not. The reason would be because the augmenting effect of the sharp increase on SBP might more than offset the dampening effect of the modest resistance decrease, whereas the augmenting effect of the blunted increase might not. Measures of SBP are easier to obtain than measures of heart contractility. Consequently, effort investigators have been especially likely to employ them despite their limitations and required cautious interpretation.

With Obrist’s hypothesis in place, the integrative analysis applies Brehm’s motivation intensity theory (MIT; Brehm and Self 1989; Richter 2013; Wright 1996, 2008) and an ability extension from it (Ford and Brehm 1987; Wright 1998; see also Kukla 1972) to identify conditions under which people should display more and less effort and associated CV responses when presented a performance challenge, i.e., a chance to alter some course of events by acting.

3.1 Motivation Intensity Theory

In brief, MIT asserts that effort is determined directly (proximally) not by factors associated with success importance (e.g., need, incentive value) but rather by what can, will, and must be done to achieve a purpose driving behavior. If the purpose can be achieved easily, then performers should exert little effort regardless of how important they perceive success to be. As the difficulty of achievement increases, so should effort up to one of two points (i.e., difficulty levels). The first is the point at which effort requirements are no longer justified by the significance (i.e., importance) of the driving purpose. The other is the point at which purpose achievement is viewed as impossible. In short, effort should comport with difficulty until success is viewed as excessively difficult—given the benefit that may be accrued—or impossible. So long as success is possible, its importance should moderate the relation between difficulty and effort. That is, its importance should determine whether the requirements of a challenge are justified and, thus, whether effort will be proportional to difficulty or low.

Fundamental relations among effort, difficulty, and success importance are depicted in Fig. 19.1a. This figure presents a case in which importance sets the upper limit of effort exertion. Presentation of a case in which impossibility sets the upper limit would show a drop in effort prior to the point (difficulty level) at which effort intersected with the horizontal importance line.

Fig. 19.1
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Effort intensity as a function of difficulty and success importance (Panel A) and difficulty, success importance and ability (Panel B)

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3.2 Ability Extension

Ability has been incorporated into the integrative analysis through the intuitive assumption that less capable (i.e., low-ability) performers view relevant performance challenges as more difficult than more capable (high-ability) performers (Hockey 1997; Kanfer 2011). This implies that low-ability performers should exert more effort than high-ability performers so long as they view success as possible and worthwhile (Fig. 19.1b). It also implies that low-ability performers should withhold effort at a lower difficulty level than should high-ability performers, because they should conclude more readily that success is either excessively difficult or impossible for them. Where both low- and high-ability performers view success as excessively difficult or impossible, ability should bear no relation to effort, being low for both groups. In theory, success importance should moderate the relation between ability and effort at a given difficulty level so long as success is perceived as possible. Thus, for example, ability might be inversely correspondent to effort at a modest difficulty level if importance is high (reflecting stronger striving where ability is low), but directly correspondent to effort at this difficulty level if importance is moderate (reflecting stronger striving where ability is high—see Fig. 19.2).

Fig. 19.2
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Effort intensity for low- and high-ability performers at a modest difficulty level where success importance is high (Panel A) and moderate (Panel B)

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4 Financial Investment Metaphor

Our effort thinking can be elaborated through use of a financial investment metaphor (Wright 1998, 2008; Wright and Kirby 2001; for a similar use, see Kruglanski et al. 2012). We envision effort as a finite currency invested following a principle of conservation. We see performers as having an upper limit on how hard they can try and being inclined to expend effort, (1) only to the degree it is needed and (2) only under conditions where it yields a return that exceeds its own value. Difficulty in this metaphor corresponds to the price of an item that might be purchased. As the price increases, so does the currency performers invest so long as the price is justified and the purchase is possible. If the price exceeds what performers can “pay” or are willing to pay, no investment will be made. Where a purchase is impossible, effort should be low because its expenditure will yield no benefit. Where a purchase is possible, but not justified, effort should be low because its expenditure will yield a return of insufficient value.

We connect ability in this context with the value—or purchase power—of the effort currency that is available. We see high-ability performers as having more valuable currency than low-ability performers. That is, we see them as being able to accomplish more at any given effort level than low-ability performers in the same way that travelers carrying a high-value currency can purchase more at any unit investment level than travelers carrying a low-value currency. Just as low-value travelers will have to expend more to meet a possible and worthwhile price, so will low-ability performers have to expend more to meet a possible and worthwhile performance challenge. Similarly, just as low-value travelers will disengage from the purchase process at a lower price point, so will low-ability performers disengage from goal pursuit at a lower difficulty level. Even high-value travelers can be confronted with a price that they cannot or will not meet. At and beyond this price point, these travelers should hold their cash in reserve in the same way that travelers with low-value currency should, rendering null the relation between purchase power and currency investment. In like fashion, high-ability performers can be confronted with challenges that they cannot or will not meet. At and beyond this difficulty level, the performers should hold their effort in reserve as low-ability performers should, rendering null the relation between performance capacity and effort investment.

We might note in discussing this metaphor that, insofar as we know, published depictions of MIT do not spell out our assumption that performers have an upper limit on how hard they can try. However, the assumption comports with MIT reasoning regarding the impossibility of success and has intuitive appeal. Further, it has been implicit in elaboration regarding the role ability should play in determining effort intensity. In context of the financial investment metaphor, the finite effort performers have available is analogous to finite cash travelers might have in their wallet or purse. For travelers, purchase will be impossible if the value of available cash is insufficient to meet a given price. For performers, success will be impossible if the performance product of maximum effort is insufficient to meet a given performance demand.

5 Fatigue as an Ability Factor

Before returning to behavioral restraint , we might note further that a number of recent experiments have examined effort correlates of fatigue construing fatigue as one factor that can determine performance ability (see Wright and Stewart 2012, for a review). In combination with the ability reasoning discussed above, this construal intimates that fatigue should not have a single effort influence, but rather a multifaceted one—sometimes augmenting effort, sometimes retarding it, and sometimes having no effect on it. Broadly, fatigue should combine interactively with difficulty and success importance to determine the extent to which performers apply themselves in meeting a performance challenge. Interactional relations among effort, difficulty, success importance, and fatigue can be seen in Fig. 19.1b, replacing the label “ability low” with “fatigue high” and the label “ability high” with “fatigue low.” The recent fatigue experiments have conceived of fatigue in terms of resource depletion within a performance system and are strongly relevant to an influential limited resource analysis of self-regulatory control developed by Baumeister et al. (2007; Lopez et al., this volume; Muraven and Baumeister 2000; Vohs et al. 2008). The limited resource analysis has a similar fatigue conception and is discussed in more detail below.

6 Intensity of Behavioral Restraint

So what might this integrative reasoning tell us about the intensity of behavioral restraint? Application begins with the understanding that urge resistance is a purpose that can be pursued more or less intensively, with pursuit (i.e., restraint) intensity arguably affected by at least three factors . One intensity factor is the value that people place on restraint, that is, how important they consider self-regulatory success to be. Another is the magnitude of the urge that must be resisted. A third is the ability of the individual experiencing the urge to resist. In the subsections that follow, we discuss these factors and the roles they should play in determining restraint intensity—taking the integrative analytic view.

6.1 Importance of Regulatory Success

The perceived importance of self-regulatory success should affect the intensity of resistance because it should determine people’s willingness to work to resist an urge. Higher importance appraisals should be associated with greater willingness. This factor must be considered in models of resistance intensity because there is reason to believe that importance appraisals vary markedly across situations and people.

6.1.1 Situation Variation

It is more important to restrain in some situations than in others. Reasons can be related to social norms, as might be the case for an individual resisting the urge to cough at a concert hall as opposed to a doctor’s office. But they will not necessarily, pertaining instead to nonnormative costs and benefits. Consider for example a soldier on the wrong side of enemy lines. She might refrain from crying out when she steps on a nail—not to abide by a norm, but rather to avoid capture. Some situations are broadly conducive to behavioral restraint , whereas others are conducive in a highly specific fashion. Specific conduciveness would apply to (1) particular urges, (2) particular people, and (3) particular urges in particular people. Consider in this regard a funeral, which can include norms that call for global respectful reserve in nonintimates of the deceased, but allow for overt expressions of grief (but not, say, erotic joy) among intimates.

6.1.2 Person Variation

Some people place greater value on restraint than do others. Once again, reasons can be variable, having to do with such things as culture, religious training, family background, and experience with outcomes that are believed to have followed from low or high self-control (Lu et al. 2012). People can place a broad premium on restraint or a premium that is more specific. Specific premiums would apply to (1) particular urges, (2) particular situations, and (3) particular urges in particular situations. Thus, for example, a Christian evangelical from the south of the USA might have a value system that calls for resistance against aggressive, but not devotional, urges in a Sunday worship service, but the reverse in a Saturday football game.

6.2 Urge Magnitude

Also affecting restraint intensity should be the power with which an urge is felt. Urge magnitude should be influential because it sets the external difficulty of the restraint challenge, with restraint being more difficult in the presence of a more powerful urge. By “external,” we mean the difficulty of the restraint challenge not taking resistance ability into account. Once again, this factor must be considered in models of restraint intensity because there is reason to believe there are marked variations moving across situations and people.

Points of note regarding situational and personal variations in urge magnitude are similar to those pertaining to situational and personal variations in restraint importance. Some situations can be assumed to be more evocative of urges than others. Some are broadly evocative whereas others are specifically evocative, that is, evocative (1) in regard to a limited set of urges, (2) for a limited set of people, or (3) in regard to a limited set of urges for a limited set of people. Examples might be political conventions and family gatherings that include discordant members, respectively. Political conventions can evoke a range of (e.g., inspirational) urges in many attendees (broad evocativeness); by contrast, family gatherings with discordant members can evoke a narrow set of (e.g., hostile) urges in some, but not all, attendees (specific evocativeness).

Just as some situations are likely to be associated with stronger urges, so might be some people. That is, it is reasonable to assume that some people experience urges more intensively than others. They could do so broadly, as has been discussed in regard to personality dimensions such as impulsivity , extroversion, and sensation seeking (Eysenck et al. 1985; Revelle 1997; Zuckerman 2009). Alternatively, they could do so specifically, in regard to limited urges, in limited situations, or in regard to limited urges in limited situations. Thus, for example, teenagers as a group might feel some (e.g., erotic), but not other (e.g., nurturing), urges with special strength when presented some—but not all—relevant stimuli.

6.3 Ability to Resist

The third intensity factor identified, ability to resist, has been discussed widely, but not always with discussions including a clear articulation of what should make people more and less restraint-capable. The most developed and influential ability position is seen in the limited resource analysis mentioned earlier (Lopez et al. this volume; Muraven and Baumeister 2000). In its most familiar form, this analysis holds that self-regulatory (i.e., behavioral) restraint involves a special inhibition system that functions like a muscle. Comparable to a muscle, the proposed system can become resource depleted (i.e., fatigued) and thereby weakened in the short term through use. Also like a muscle, the system can be strengthened through extended use over time. The limited resource analysis implies that people can vary in restraint ability both in the short term and in the long term, with short-term variations reflecting degrees of fatigue and long-term variations reflecting degrees of strength. Ability discussed in this sense should affect restraint intensity because it should combine with the magnitude of an urge experienced to determine what must be done to resist. Holding urge magnitude constant, people with low restraint ability should have to do more to resist than people who have high restraint ability.

6.4 Roles of the Restraint Intensity Factors Taking the Integrative View

With the restraint intensity factors discussed in these terms, it is easy to see the roles they should play in determining restraint intensity taking the integrative analytic view. As illustrated in Fig. 19.3a, restraint value (i.e., regulatory success importance) appraisals should set the upper limit of what people would be willing to do to restrain, but not determine restraint intensity directly, as some might suppose. What should determine restraint intensity directly is the difficulty of the restraint challenge, which should be a function of the magnitude of the urge resisted. Where resistance is perceived as possible and worthwhile, its intensity should be proportional to difficulty. Where resistance is perceived as impossible or excessively difficult—given the importance of regulatory success—resistance should be low, with importance appraisals moderating the relation between effort and difficulty so long as success is perceived as possible.

Fig. 19.3
figure 3

Restraint intensity as a function of urge magnitude and value placed on success (Panel A) and urge magnitude, value placed on success and restraint capacity, including that associated with fatigue (Panel B)

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Also contrary to what some might suppose, restraint ability should not exert a single influence on restraint, but rather a multifaceted influence dependent on the difficulty of the restraint challenge and the value placed on meeting it (Fig. 19.3b). Where both low- and high-ability restrainers view success as possible and worthwhile, restraint intensity should be (1) correspondent to difficulty for both groups and (2) greater for the low-ability group by a constant. Where high-ability restrainers view success as possible and worthwhile, but low-ability restrainers do not, restraint intensity should be (1) low for the low-ability group and (2) correspondent to difficulty for the high-ability group. Where difficulty and value appraisals are such that neither low- nor high-ability restrainers view success as possible and worthwhile, restraint intensity should be low for both groups.

7 CV Correlates

Of course, the integrative analysis addresses not only effort but also CV responses associated with it, assuming proportionality between effort intensity and beta-adrenergic SNS activation. The CV component suggests that the regulatory success importance, urge magnitude, and restraint ability factors discussed above might combine interactively to determine the intensity of this class of CV responses in the same way that they should combine to determine restraint intensity. Just as restraint intensity should first rise and then fall abruptly with the difficulty of a restraint challenge (i.e., the magnitude of an urge), so might the relevant CV responses—with the importance of regulatory success moderating the relation between difficulty and the responses so long as success is possible. Similarly, just as restraint intensity should bear different relations to restraint ability under different regulatory success importance and difficulty (urge magnitude) conditions, so might these CV responses. In short, all the relations indicated for restrain intensity in the panels of Fig. 19.3 might also hold for beta-adrenergic responsiveness.

8 Direct Evidence

Direct evidence for this application of the integrative analysis is undeniably thin. It consists chiefly of findings from two types of experiments, ones that show (1) elevated CV responses in participants directed to resist an impulse (Gross 1998; Gross and Levenson 1993; see also Wegner et al. 1997) and (2) elimination of self-regulatory performance deficits in “ego” (i.e., resource)-depleted participants under incentivized performance conditions (Muraven and Slessareva 2003). The findings comport with the notion that restraint requires work that can enhance CV activity and be promoted through the provision of incentives. However, they do not evaluate the nuanced implications of the application, such as the implication that resistance and associated CV responses should bear different relations to restraint ability under different success importance and difficulty (urge magnitude) conditions.

9 Indirect Evidence

On the other hand, indirect evidence for the application—from nonregulatory tests of the integrative analysis and its application—is abundant. Early reviews of the relevant literature considered data from studies that involved a variety of protocols and effort intensity indices (e.g., Brehm and Self 2001). Later reviews focused on CV studies, which emerged as the largest component of the full body of evidence (Gendolla and Richter 2010; Gendolla and Wright 2005; Gendolla et al. 2012). Collectively, the reviews revealed remarkable support.

9.1 Simple Examples

To provide a flavor, consider a simple CV response study by Richter et al. (2008). Expanding on work by Obrist et al. (1978), Smith et al. (1990), Wright et al. (1986), and others, the investigators presented participants trials of a character recognition task whose difficulty varied across four levels, ranging from low to impossibly high. For some participants (mild challenge), the initial character string was displayed for 1000 ms; for others (moderate challenge), the string was displayed for 550 ms; for a third group (strong challenge), the string was displayed for 100 ms; for a final group (impossible challenge), the string was displayed for 15 ms. As expected, SBP and heart contraction (pre-ejection period, or PEP) responses assessed during performance rose steadily across the first three difficulty conditions and then fell (Fig. 19.4).

Fig. 19.4
figure 4

Pre-ejection period (PEP—Panel A) and systolic blood pressure (SBP—Panel B) responsiveness at four levels of task difficulty. Bars indicate standard errors. Note that lower PEP values indicate increased heart contraction force. (From Richter et al. 2008—reprinted with permission from John Wiley and Sons, also seen in Fig. 24.2 in Gendolla et al. 2012)

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Also consider an experiment by Silvia et al. (2010) that examined interaction implications in an objective self-awareness (OSA) theoretical context (see Silvia, this volume). OSA theory (Duval and Wicklund 1972) asserts that self-focus draws attention to where one stands in regard to performance standards, elevating the importance of meeting them. Applying the integrative analysis, an implication is that self-focus should moderate the relation between difficulty, on the one hand, and effort and associated CV responses, on the other, so long as task success is possible. Investigators presented participants a more or less difficult scanning task (d2; Brickenkamp 1981) under conditions more or less conducive to self-focus, using a mirror focus manipulation. Easy participants had 3000 ms to scan; difficult participants had 650 ms to do so. Analysis of SBP data collected during performance showed the expected 3 versus 1 response pattern. Responsiveness was correspondent to difficulty when self-focus was high, but low irrespective of difficulty when self-focus was low.

9.2 Ability Construed as Fatigue

Illustrative of studies that evaluated more complex influences are two CV experiments that crossed difficulty and ability factors operationalizing ability in terms of fatigue , assuming lower ability among more fatigued participants. These are especially relevant to the restraint application because so much attention has been devoted to the Baumeister limited resource model of self-control. One experiment (Wright et al. 2003) examined the idea that mental fatigue should augment or retard effort and associated CV responses depending on whether it causes success to be perceived as excessively difficult or impossible. Participants performed an easy (fatigue low) or difficult (fatigue high) counting task for 5 min. They then were presented mental arithmetic problems with the chance to earn a prize if they attained a low (30th percentile) or high (80th percentile) performance standard. Analysis of second period SBP responses revealed a fatigue × standard (difficulty) interaction, with means in a crossover pattern (Fig. 19.5). Analysis of diastolic blood pressure (DBP—the trough pressure following a heartbeat) and mean arterial pressure (MAP—average pressure across a heart cycle) data revealed the same interactions and mean configurations.

Fig. 19.5
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Systolic blood pressure (SBP) responsiveness as a function of difficulty for low- and high-fatigued participants. Bars indicate standard errors. (Based on data from Wright et al. 2003—also seen in Fig. 24.4 of Gendolla et al. 2012)

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The other experiment (Stewart et al. 2009) evaluated the implication that success importance should moderate the relation between mental fatigue, on the one hand, effort and associated CV responses, on the other, at a given difficulty level so long as success is possible. It first manipulated fatigue by requiring participants to perform an easy (fatigue low) or difficult (fatigue high) paced scanning task (version of the d2) and then presented the participants mental arithmetic problems with instructions that they would earn a high or low chance of winning a prize if they did as well as 50 % of those who had performed previously. Investigators assumed that extra demand associated with fatigue would be justified when the chance (i.e., success importance) was high, but not when it was low (Bandura 1982; Vroom 1964). Consequently, they anticipated fatigue augmentation of effort and associated CV responses under high-, but not low-, chance conditions. Analysis of task period CV responses confirmed the prediction for SBP and revealed similar DBP and MAP response patterns.

10 Summary and Concluding Comments

We have sketched here an understanding of behavioral restraint intensity and CV responses that may accompany it. The understanding represents an application of an integrative analysis that has guided research in our laboratory and has distinctive implications relative to traditional self-regulation perspectives. One core idea is that restraint intensity varies proximally with the magnitude of the urge resisted—first rising and then falling, with the fall occurring where regulatory success appears impossible or excessively difficult given its importance. Another is that restraint ability factors have different influences on restraint intensity depending on the magnitude of an urge and the importance of resisting it. This second idea has special relevance to the Baumeister limited strength model of self-regulation , which articulates how people can become more and less restraint-capable through short- and long-term efforts to maintain behavioral control. CV responses accompanying restraint intensity may be those associated with beta-adrenergic SNS activation, most often assessed in terms of heart contraction force and SBP. Direct evidence for this understanding is limited, but indirect evidence—from nonregulatory tests of the integrative analysis and its application—is abundant.

The sketched understanding is noteworthy in part because it has potential for improving prediction of regulatory successes and failures, which can—but will not necessarily—correspond to how hard restrainers try. It suggests for example that where the effort-to-performance relation is favorable, success importance factors should tend to predict performance if those factors determine whether the effort required to meet a possible restraint challenge is justified, but not if they do not determine this. If the factors determine whether the required effort is justified, restraint intensity should be greater and regulatory success should be more likely under high-importance conditions. If the factors do not determine whether the required effort is justified—in other words, if the effort is or is not justified at all levels of the factors—restrain intensity and success likelihood should be dissociated with success importance (see Fig. 19.3a). The understanding is noteworthy as well because it has potential for improving prediction of adverse health outcomes that might follow from restraint. It identifies conditions under which possibly health-toxic restraint efforts should occur in different degrees and suggests for example that chronic regulatory system fatigue might (1) be associated with health risk when it does not alter the perception that regulatory success is possible and worthwhile, but (2) not be associated with health risk when it does (Fig. 19.3b).

The suggested link between restraint intensity and the magnitude of certain CV responses draws attention to pathways through which restraint might negatively impact health. In particular, it draws attention to the so-called reactivity hypothesis, which delineates (e.g., mechanical) outcomes that can accompany persistently exaggerated CV responses and lead to pathological endpoints (Kamarck et al. 1997). This hypothesis cannot account for all adverse health outcomes that have been linked to resistance, but it can reasonably be supposed to account for some, such as hypertension. The suggested link also presents the possibility that resistance might be assessed covertly via careful tracking of beta-adrenergic SNS adjustments.

We feel comfortable with this understanding as a model of restraint intensity, but recognize that it is not a final product. There is much empirical work to be done to establish the validity of the core ideas. There also is conceptual work to be done, for example, regarding additional factors that might be incorporated. Concerning additional factors, special thought might be devoted to the value that performers place on restraint resources. There is reason to believe this can vary and have an impact on the willingness to work (Kruglanski et al. 2012; Muraven et al. 2006).

A question relevant to this and all other discussions of behavioral restraint is what determines the presence and intensity of behavioral urges (Frijda 1986). The answer is critical because it tells us when resistance in different measures can occur. Investigators commonly assume that urges are evoked by salient outcomes and vary to the degree that those outcomes have personal significance (“relevance”). However, this almost certainly represents an oversimplification. It is beyond our scope here to delve into this issue, but we can conclude by referring readers to a sister theory of MIT—Brehm’s emotion intensity theory (EIT)—for possible direction. EIT has received modest attention since it was proposed, but represents one of the most sophisticated treatments of behavioral urges to date. Central presentations (e.g., Brehm 1999) should be required reading for all serious students of regulatory control.