Theories of Impulse
Expectancy-value models can describe the careful planning behind the Trojan horse well, but they seem less able to explain why Icarus would immolate his wings. The kind of action implied in the latter myth is apparently not influenced by the knowledge of the action’s expected consequences. It may rather be seen as reckless, as based on an impulse that seems to instigate behavior automatically. This determinant of behavior differs from the rational assumptions of Socrates or the theory of planned behavior (Fishbein & Ajzen, 1975) and must be explained by other means. Historically, this point is recognized by Aristotle in the Nicomanchean Ethics (Crisp, 2000) when he argues that people may at times act against their judgment. In his view an overwhelming passion—physical feelings (e.g., hunger) and emotions (e.g., fear or pleasure)—directly implies a practical conclusion to act on it. This practical conclusion may at times overpower the conclusions reached by reason.
Psychology as a discipline has focused mostly on factors that affect the ability of reasoned conclusions to control passionate ones (Hofmann, Friese, & Strack, 2009). For example, children’s ability to forgo a small, immediate reward in favor of a larger, delayed reward has been shown to depend on various factors, including opportunity to pay attention to the immediate reward and thinking happy or sad thoughts (Mischel, Ebbesen, & Raskoff, 1972). Muraven and Baumeister (2000) conceptualize the control of impulses as being achieved by a metaphorical “muscle” that is powered by limited resources and is subject to fatigue, a state called ego depletion. In this view, reasoned control of impulses will fail if remaining resources of self-control are insufficient to overcome impulse strength. Personality variables have been linked to the ability to control impulses (e.g., Block & Block, 1980; Carver, 2005), as have physiological variables such as blood glucose and alcohol levels (Bushman & Cooper, 1990; Gailliot et al., 2007) and situational factors such as the availability of tempting stimuli (Schachter, 1971).
Another approach to impulses and their effect on behavior is provided by research on implicit attitudes. Implicit attitudes are seen as spontaneous, automatic affective and behavioral responses to attitude objects (Greenwald & Banaji, 1995). The view that impulsive behavior comes from overwhelming passion caused by a situation maps well onto this idea that attitude objects may spontaneously cause affect and behavior via automatic processes. This view contrasts with the position that attitudes are evaluations of target objects (e.g., Eagly & Chaiken, 1993). The evaluative position implies a more deliberative assessment of object properties, which corresponds to processes similar to those described in the theory of reasoned action (Fishbein & Ajzen, 1975). Researchers studying implicit attitudes generally adopt indirect attitude measures such as the affective priming paradigm (Fazio, Sanbonmatsu, Powell, & Kardes, 1986) or the implicit association test (IAT) (Greenwald, McGhee, & Schwartz, 1998). These instruments typically use a combination of valent and categorical stimuli and measure their inhibition or facilitation of a target behavior. Affective priming studies show that people categorize evaluative adjectives such as good or bad faster when they are congruent in valence to an attitude object shown immediately beforehand (Fazio, 2001). The IAT measures the difference between reaction times when participants are asked to categorize an object by attitudinal categories via a key-press reaction also associated with a particular valence (Greenwald et al., 1998) . These measures show that behavioral responses to specific stimuli are influenced by the valence of these stimuli. The difference between what these implicit measures capture and what traditional evaluative measures (e.g., self-report questions) assess is apparent from their only moderate correlations (Fazio & Olson, 2003) and by the relative robustness of implicit measures with regard to participants’ conscious control (Banse, Seise, & Zerbes, 2001; Kim, 2003; but see Mierke & Klauer, 2001, and Fiedler & Bluemke, 2005, for critical discussions). One explains these results by stating that the spontaneous response to an attitudinal object is governed by associations that may differ in content from the results of a deliberative evaluation. These associations occur between perceived objects, behavior, and affect. The link between impulse and behavior has some theoretical basis—including the ideomotor principle (James, 1890) and the perception- behavior link (Bargh, 1997)—as does a direct link between perception and affective response (Zajonc, 1980). However, research on implicit attitudes has not succeeded in explaining what an implicit attitude actually is, beyond the tautological functional definition that an implicit attitude is what is measured by indirect measures (Strack & Deutsch, 2007). With evidence accruing that implicit attitudes may be strongly affected by the context (Wittenbrink, Judd, & Park, 2001) and type (Bosson, Swann, & Pennebaker, 2000) of the measurement, the question of what exactly an impulse might be is becoming ever more relevant.