Copyright © by Alan J. Fridlund, All Rights Reserved.
The current version benefitted from the editorial efforts of Andrea Scarantino. An expanded version will appear in a volume published by Oxford University Press.
August 2015 – I began as an adherent of the Basic Emotions Theory (BET) of facial expressions. In most formulations, BET held that emotions, understood as internal states or discrete affect categories, were associated with specific patterned movements termed “facial expressions of emotion.” The foundation for BET was research in which members of diverse cultures matched a small number of photos of posed facial expressions to a similarly small number of emotion terms, suitably translated or mapped onto stories (Ekman, 1972; Ekman & Friesen, 1971; Ekman, Sorenson & Friesen, 1969; Izard, 1971).
These matching-to-sample studies, jointly with other evidence, were declared to mean that: (1) the emotions signified by the terms/stories were “biologically based,” i.e., they were phylogenetic; (2) the emotional facial expressions matched to the emotion terms were uniform in their production and universal in their recognition; and (3) there was an automatic, causal link between the prototypical emotional faces and the respective internal emotional mechanisms (collectively, the “Facial Affect Program”) that produced them. In BET, any deviation from the predicted correspondence between a triggered emotion and the emission of its counterpart facial expression was due to the intervention of cultural “display rules” governing social behavior (Ekman & Friesen, 1969). Such culturally dependent control was imperfect, however, and so a muted, throttled or distorted expression might “leak” traces of the suppressed, genuine emotion of the expressor onto the face.
At the start of my career, BET was the dominant framework for studying emotion and facial expression, and I had no reason to challenge it. I began by conducting electromyographic studies of the tiny facial movements people made during emotional imagery (Fridlund, Schwartz & Fowler, 1984), work begun by Paul Fair and Gary Schwartz (Schwartz, Fair et al., 1976). Gary invited me to his Yale lab to conduct my doctoral studies, and introduced me to Silvan Tomkins. Later he arranged for me to meet Carroll Izard and Paul Ekman, the two leading BET theorists at the time. I came to know both men well, and I may be the only person to have written papers with each (Ekman & Fridlund, 1987; Fridlund, Ekman, & Oster, 1988; Fridlund & Izard, 1983; Matsumoto, Ekman, & Fridlund, 1990). Over time, however, I developed unresolvable disagreements with them over the tenets of BET.
My skepticism about BET came from four growing realizations: (1) the cross-cultural findings could never have been helpful in apportioning roles to “biology” vs. “culture,” because both diversity and uniformity can arise from natural selection (think finches); (2) claiming cross-cultural uniformity for certain iconic facial expressions after obtaining matches to emotion categories, and universality of those “basic emotions” based on the same matches, was circular and tautological; (3) on closer inspection, the matching between facial displays and emotion terms/stories began to appear inflated to me and other researchers, due to technical deficiencies in the experimental protocols; and, most important, (4) regarding the face as an automatic but suppressible readout of internal, “authentic” emotional states conflicted with modern views of animal communication. This last point was most critical in convincing me that BET was fatally flawed.
Darwin first attempted systematically to link animal signaling with our facial expressions, and BET theorists duly pay homage to him, but misread him when they cite him to support their claim that our facial expressions evolved “to express emotion” (see Fridlund, 1992a). In promulgating evolution by natural selection, Darwin had first to dispose of a contending position: the Argument from Design, made by Charles Bell, William Paley and others, which held that creatures were well-suited to their niches because God made them so. Thus, in On the Origin of Species, Darwin could not repeat identical evidence of goodness-of-fit and then argue a different conclusion. Instead, he used evidence of imperfect design – vestigial structures such as webbed feet on land birds, phalanges in a seal’s flipper, and the human appendix – as proof of common origins and to vitiate notions of perfect design ex nihilo (Browne, 1985; Darwin, 1859; Fridlund, 1992a; Gruber, 1974).
In The Expression of the Emotions in Man and Animals, Darwin extended his assault on the Design argument to Bell’s view of facial expressions: “I want, anyhow, to upset Sir C. Bell’s view … that certain muscles have been given to man solely that he may reveal to other men his feelings” (F. Darwin, 1887, Vol. 2, p. 78.). He proposed instead that, as with vestigial organs, most facial behaviors were likewise rudimentary and “of no service, often of much disservice,” or “purposeless” (Darwin, 1872, pp. 67, 76). They were either remnants of reflexes that had been useful (“serviceable associated habits”), antithetical remnants arising from contrasting elicitors (“antithesis”), or overflows of excitation (“direct actions of the nervous system”). Any communicative value for facial expressions was incidental. Although Darwin’s account neutered Bell’s creationism, it left him unequipped to argue that facial expressions evolved for anything (Fridlund, 1992a).
While honoring Darwin, BET actually co-opted the 1950’s mechanistic ethology of Lorenz and Tinbergen (Lorenz, 1967, 1970; Tinbergen, 1952, 1953). These early ethologists’ tripwire fixed-action patterns became the “Facial Affect Program” of the neurocultural version of BET (even the “FAP” acronyms were identical; Fridlund, 1992b). Instead of red spots on beaks that released appeasement displays and food calls, prototypical emotional events triggered the release (“expression”) of emotion that spilled out on our faces and reflected our “true feelings” except if modified by tradition (“display rules”), training, or treachery.
If BET was drawing upon the Lorenz-Tinbergen formulations, modern ethology was abandoning them, leaving BET gutted of its claim to Darwin’s imprimatur and severing BET from any continuity with developing models of animal communication. Animal behaviorists began to note that most nonhuman signals didn’t look fixed or cartooney, but flexible, social and contextual (Alcock, 1984; Hinde, 1985a, b; Smith, 1977). Such behavioral ecologists (cf., Davies, Krebs, & West, 2012; Maynard Smith, 1982) saw animal signaling not as vestigial reflexes, or readouts of internal state, but as adaptations that served the interests of signalers within their social environments. Signaler and recipient – even when predators and prey (e.g., “pursuit deterrence” signals; see Caro, 2005) – were reconceived as coevolved dyads in which displays indicated the likely behavior of issuers, with recipients using such behavior as cues to the issuers’ next moves (Krebs & Davies, 1987; Krebs & Dawkins, 1984).
Although Darwin’s vestigial reflexology in Expression was outdated, it seemed to me that modern behavioral ecology’s view of expressive behavior as dynamic and contextual offered a way to resurrect Darwin’s grander vision of continuity between human and nonhuman signaling. Thus, in the 1990’s, I began writing position papers and conducting studies on what became the Behavioral Ecology View (BECV) of human facial behavior. In this account, human facial displays, like animal signals, serve the momentary “intent” of the displayer toward others in social interaction (Fridlund, 1990; 1991a, b; 1992a, b; 1994; 1996; 2002; 2006). (“Intent” here is adduced from people’s interactional trajectory; it does not presuppose that people know, can articulate, and/or will disclose what they intend).
Indeed, many of the classic, iconic BET expressions can be recast in such intentional, functional terms. In suitable contexts, so-called “happy faces” solicit affiliation or play, whereas “sad faces” recruit succor, “anger faces” threaten or deter, “fear faces” predict submission or withdrawal, “disgust faces” indicate rejection or intent to spew, and so on (see Table 1 below).
When participants are asked to match iconic BET expressions to functional redescriptions (e.g., “back off or I’ll attack”), such redescriptions achieve matching rates equal to emotion terms (e.g. “anger”; Yik, 1999). Unlike emotion terms, however, these functional descriptors imply neither any particular internal state (e.g. one can solicit affiliation or play when happy or unhappy), nor any moral assignations about which signals are “honest” or “genuine” (e.g. a face recruiting succor is not “honest” because one is sad and dishonest when one is not). Such functional descriptions are predicated merely on the view that facial displays are only probabilistic signals of social intentions that would, in everyday life, be accompanied by the words, vocal prosodies, and gestures congruent with the intent.
According to BECV, facial displays serve as social tools. To wit, in accusing a relationship partner of committing an infidelity, one might exclaim, “You are a stinking, lying turd!” and supply the concordant tone of voice, an upturned nose, and the appropriate hand and finger gestures. All this sound and fury would force a nixing or resetting of the relationship. For BECV, understanding that the shock-and-awe display was a tool for relationship realignment is all it takes to explain why the signaling occurred. Any detour to qualia (or other internal proxy for emotion) as causal is extraneous because, in BECV, there is no necessary connection between those signals and any one emotion: the accuser/displayer may have been disgusted, contemptuous, devastated, livid – or relieved or thrilled, if the entire rejection drama was staged to divert the partner from discovering that he/she cheated first.
BET advocates objected to this interactional view of facial displays, noting that “Facial expressions do occur when people are alone … and contradict the theoretical proposals of those who view expressions solely as social signals” (Ekman, Davidson & Friesen, 1990, p. 351). It was necessary, therefore, to explain that being alone physically didn’t imply that we were alone psychologically.
In this social media age, when people have their faces glued to their phones and begin and end relationships with right and left swipes, this explanation now seems obvious, but it was originally contentious. From the start, I had enumerated examples in which we were alone but implicitly social (Fridlund, 1991a): imagining or misbelieving that others are present (daydreams, flashbacks, or talking to someone who’s left the room), grieving (when we crave reunion), sexual fantasy, soliciting an interaction (recruiting succor with a pained or crying face, as infants do), or preparing for one (rehearsing for a play or interview).
In all these cases, individuals may subvocalize – they are “talking to people in their heads” – and any accompanying “solitary” faces would be equally social. It makes no difference if the interactant is myself: If I scowl and tell myself, “Now Fridlund, don’t screw up!”, both my words (sotto voce) and accompanying face (sotto facie?) serve to keep Fridlund focused and out of trouble.
We showed this experimentally, with human studies that extended novel avian research by the much-missed Peter Marler (Marler, Duffy & Pickert, 1986a, b). We demonstrated audience effects in solitary smiling with audiences that were both explicit (friends were present) and implicit (participants were alone but believed friends were co-participants elsewhere), and with social vs. nonsocial imagery (Fridlund 1991, Fridlund et al., 1990, 1992). Several investigators have replicated such implicit audience effects, expanding the findings to infants, beyond smiling, and to augmenting vs. decrementing effects of friends vs. strangers (Hess, Banse & Kappas, 1995; Jones, Collins & Hong, 1991; Schützwohl & Reisenzein, 2012; Wagner & Smith, 1991).
BET partisans dismissed these findings peremptorily: “No account should be taken of studies that do not distinguish between Duchenne and non-Duchenne smiles…” (Ekman & Keltner, 1997, p. 41). “Duchenne smiles,” according to BET, were genuine, emotional, “felt” smiles, unlike other, intrinsically social smiles, which might be “false,” “phony” or “unfelt” (Ekman & Friesen, 1982; Frank & Ekman, 1993; Frank, Ekman & Friesen, 1993). The criticism was entirely misplaced, since in the implicit-audience studies, the smiles in question varied substantially with sociality but were all emitted in solitude – which, for BET, would make them emotional and genuine (again, Ekman et al., 1990, p. 351).
As Ruth Leys noted (personal communication, March 5, 2015), Ekman soon changed course from dismissing these implicit-sociality findings to revising his theory to accommodate them: “I expect that some display rules are so well established that some people may follow them even when they are alone. And some people when alone may imagine the reactions of others, and then follow the appropriate display rule, as if the others were present. And finally, there may be display rules that specify the management of expression not just with others but when alone” (Ekman, 1997, p. 328). Notably, Ekman did not specify how one might ascertain when such “solitary display rules” were in effect and when they were not.
If Ekman’s turnabout solved one problem, it opened up a bigger one. Prior to this change, Ekman contended that solitary facial behavior was free of display rules. Of the paradigmatic Japanese-American study cited most as a demonstration of the display-rules concept (Ekman, 1972; Friesen, 1972), Ekman summarized the findings: “In private, when no display rules to mask expression were operative, we saw the biologically based, evolved, universal facial expressions of emotion. In a social situation, we had shown how rules for the management of expression led to culturally different facial expressions” (Ekman, 1984, p. 321). With Ekman’s expansion of BET to include solitary display rules, can it now be certain that the solitary faces observed in the Japanese-American study were display-rule-free and thus “biologically based, evolved, universal facial expressions of emotion”? If so, how would that be verified?
There are wider repercussions. Ekman’s concession that private behavior may be conventional like our public behavior reduces considerably the distance between the claims posed by his neurocultural version of BET, and those struck earlier by the cultural relativists he so staunchly opposed, such as Margaret Mead and Ray Birdwhistell, who argued for the pervasiveness of cultural learning in all aspects of life.
Findings that solitary smiles could be “social” also seemed to violate BET’s felt/false, Duchenne/non-Duchenne smile dichotomy. Can this dichotomy be sustained? I proposed early on that “Duchenne” smiles were actually conjoint displays of typical smiling plus tonic elicitation of the blink reflex of Descartes (“wincing”), the latter of which could occur with any strong stimulus and not any specified emotional state (Fridlund, 1994).
Studies now indicate that, contrary to BET, Duchenne smiles are at least as affected by sociality as non-Duchenne ones (Crivelli, Carrera & Fernández-Dols, 2015; Fernández-Dols & Ruiz-Belda, 1995; Mehu, Grammer & Dunbar, 2007; Ruiz-Belda, Fernández-Dols & Barchard, 2003), that they can be produced deliberately (Gosselin, Perron & Beaupré, 2010; Gunnery & Hall, 2014; Gunnery, Hall & Ruben, 2013), and that their occurrence varies both with smile intensity (Krumhuber & Manstead, 2009) and stimulus intensity regardless of valence (Harris & Alvarado, 2005).
BECV rejects the idea that some display, or class of displays, can have intrinsic properties outside the context of its issuance. Smiles may be made by mothers toward children or assailants toward victims. Tears may flow in grief, retribution, reconciliation, or triumph. The meanings of these displays can be understood only by considering who makes them and when they occur.
In the neurocultural version of BET, however, morphology dictates not just emotionality but authenticity. Duchenne smiles are “genuine” because they are “felt,” and disingenuous because they are “unfelt” or “false.” This stark dichotomy turns everyday courtesy into mendacity. It also leads to futile diversions. A used-car salesman may be a consummate Duchenne smiler and scam nearly every customer who walks onto his lot. His winning Duchenne smiles sell cars. For BET, then, his smiles must be “felt.” Is this what we care about, whether he’s happy if he scams us?
For BECV, the “authenticity” of his smile lies not in what he feels, but in whether it predicts whether he will treat us fairly if we buy a car from him. More generally, we learn whose words and expressions are reliable indicators of their intent, and over time we bond with those individuals who prove reliable and avoid those who prove otherwise.
In deception, therefore, the “truth” of a display inheres neither in the display nor its displayer, but in the moving average by which a recipient continually calibrates and recalibrates the reliability of the signals issued in that context by that displayer. Greater predictability of displayers’ signals and lower skepticism by recipients toward those signals naturally co-evolve with repeated cooperation, else breaches occur that force recalibration, confrontation, or termination of interaction (Mitchell & Thompson, 1986). The “leakage” seen by BET theorists as the breakout of “genuine emotion” through an outer mask is simply a momentary conflict in intentions in social negotiation (Fridlund, 1991a). This interactional perspective is decidedly anti-Darwin qua Expression but resoundingly Darwinian (Fridlund, 1992a).
Certain questions have been raised repeatedly about BECV. Does BECV deny “emotion”? Does BECV deny a privileged relationship between “emotion” and certain facial displays? Do “emotions” serve as “commitment devices” that reveal our authentic, internal states (Frank, 1988; and see crucial treatment of the emotion-as-commitment issue by Leys, 2013)? To BECV, all these questions mean little, because they hinge entirely on how one defines emotion (cf., Schattschneider, 1960; to paraphrase: defining the terms determines the outcome). Over a century’s theory and research have demonstrated that “emotion” has proven intractable to consensual, let alone operational, definition.
BET theorists often identify “emotion,” at least implicitly, with qualia or “feelings.” For example, an observer may claim that someone “felt sad” and his sadness produced his “sad expression.” In the neurocultural version of BET, “felt” (“Duchenne”) smiles are “all smiles in which the person actually experiences … a positive emotion” (Ekman & Friesen, 1982, p. 242). Both the “sadness” and “positive emotion” contentions make qualia – or their putative proximal generators – causal, and both are untenable when they make accountable something ineffable and unverifiable.
But what if one were to localize the proximal generators for qualia, the “feeling centers,” in the brain? Could we then say that changes in qualia, or those generators that produced the qualia changes, caused the associated events in the neuromuscular centers that produced the facial expressions? How does one ever determine that event A causes event B in the brain? I invite readers new to this question to Google “Libet’s experiment” and discover the labyrinthine complexities in determining neurocausality.
One common BET recourse to according qualia strict agency and keep “emotion” scientific is to make facial expressions just part of the package of changes (neurochemical, behavioral, cognitive) that constitutes an emotion or “affect program,” qualia being among them. On this view, the presence or absence of emotion cannot be determined by the presence or absence of qualia, or of any other single component or subset of components.
This view reduces to no more than hand-waving about the knottiness of the phenomena and ad hoc choices of stipulated “emotion measures,” with the result that surveys of research and formal meta-analyses continually find disappointing links between “emotion” and “expression” (cf., Ortony & Turner, 1990). Newer backstops include: (1) trying to re-objectify “emotion” as a neo-Kantian, categorical “conceptual act” that belongs more to the observer than the emoter (Barrett, Wilson-Mendenhall, & Barsalou, 2015), and (2) paradoxically trying to nail down the “emotion” concept by declaring it intrinsically fuzzy (Scarantino & Griffiths, 2011).
For BECV, all this reasoning is tendentious and wasteful if the purpose is to understand our facial displays. The same holds for ecumenical BET formulations that begin with emotion, variously defined, and end with how “everyone knows” that the expressions have social functions, too (e.g., Hauser, 1996). For BECV, displays evolved as social tools directly, not as parts of underlying mechanisms for the production of displays. Natural and cultural selection do not “care about” (specifically select for) the inner workings of traits, only the traits themselves.
Facial behaviors that aid individuals in navigating their social terrains (i.e., displays) will, via their displayers, tend to proliferate horizontally (i.e., culturally and geographically) and vertically (via genetic/epigenetic inheritance), regardless of what neural operations produce them; accompanying these displays is the coevolution of recipient behavior that is attentive yet skeptical (Krebs & Dawkins, 1984).
How has BECV fared against BET? James Russell’s influential critique of the cross-cultural matching-to-sample studies (Russell, 1994), and his team’s demonstration of powerful context effects in facial-expression perception (Carroll & Russell, 1996; Russell & Fehr, 1987), broke the paradigm lock BET had on facial-expression research. BECV’s small contribution has been to supply a new framework for understanding our facial displays, one that restores Darwin’s vision of human-animal continuity and places it on a solid evolutionary footing. I believe it’s what Darwin would have proposed had he been able.
I am pleased by how much serious scholarly attention BECV has received. I grounded it in behavioral ecology and evolutionary theory, but Brian Parkinson’s generous review reminded me of its debt to Dewey (Parkinson, 2005). With penetrating depth, Ruth Leys has shown how BECV can clarify philosophical and technical problems in the objectification and neural localization of emotion (Leys, 2007, 2010, 2011, 2014). BECV has informed research on both public and implicit-audience accounts of responses to social media (Litt, 2012), smiling in pain (Kunz, Prkachin, & Lautenbacher, 2013), human-computer communication (Aharoni & Fridlund, 2007), persuasion (Cesario & Higgins, 2008), power and dominance (Burgoon & Dunbar, 2006), facial displays in rats (Nakashima, Ukezono, Nishida, Sudo, & Takano, 2015) and chimpanzees (Parr & Waller, 2006), intrapersonal communication in therapeutic narrative writing (Brody & Park, 2004), and the game-theoretic analysis of human deception (Andrews, 2002).
Finally, José-Miguel Fernández-Dols and his colleagues have conducted a line of masterful studies showing how BECV can account for facial behavior in naturalistic settings (e.g., Crivelli et al., 2015; Fernández-Dols & Ruiz-Belda, 1995; Ruiz-Belda et al., 2003). It also seems that the battle royale between BET and BECV has liberated inquiry on facial expressions: investigators can now pursue hypotheses (e.g., genetic/epigenetic diversity in facial displays, facial dialects, infant deception) that, because they transgressed BET, were previously inconceivable or taboo.
BECV will always be a tough sell. It requires shaking off a romanticized view of human nature that makes the face a battleground between an “authentic self” and an impression-managed “social self” (Fridlund, 1994, 1996). The first concept we treasure; the second we concede reluctantly. To BECV, both are illusory. Like our words, voice and gestures, our facial displays – even those we make as infants, and which will be deployed by our android companions (will they have felt or false Duchenne smiles?) – are part of our plans of action in social commerce.
I am indebted to Jose-Miguel Fernández-Dols and Ruth Leys for comments and suggestions.
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