![Sample our Behavioral Sciences journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/110801/TOC-Subject-Sample-2021-Behavioral-Sciences.jpg"})
Abstract
Yawning has a well documented contagious effect: viewing or hearing a yawn—as well as talking or thinking about yawns—causes human subjects to yawn. While comparative ethological and neurological accounts suggest that yawning is a function of primitive biological structures in the brain stem, these analyses do not account for infectious yawning caused by representational and semantic states. Investigating the relationship between perceptual and cognitive avenues of yawn induction affords a unique opportunity to examine how higher level cognitive faculties interact with involuntary or automated processing systems. In this paper, I examine three distinct attempts to reconcile the cognitive properties of contagious yawning with its physiological basis—one neurological, one philosophical, and one functional. None of these accounts are unproblematic, and the most plausible hypothesis for the evolution of contagious yawning does not satisfactorily explain the cognitive iterations of the phenomenon. I argue that the most likely explanation of the contagion links perceptual elements of witnessed yawns to conceptual representations. More centrally, this kind of integrated account has repercussions for general theories of human thought and rationality, and suggests that higher level representational states engage neurophysiological structures in determining human behavior.
Notes
John Sarnecki is Assistant Professor of Philosophy at the University of Toledo.
Notes
[1] I am grateful to Robert Provine for this observation.
[2] A common theme in yawning studies is the difficulty that attends to producing yawns in laboratory environments. See Baenninger and Greco (Citation1991) for a more detailed account of this problem.
[3] Some studies have shown, for example, that even if we can’t absolutely claim that yawning is an adaptation, we can genetically manipulate its frequency and occurrence in animals through artificial selection. See Holmgren et al. (Citation1991).
[4] This is not to suggest that Morgan's canon is not unproblematic. See Sober (Citation1998) and Bennet (Citation1991) for recent interpretations of this principle. See also Montminy (Citation2005) for a more sceptical reading of its value.
[5] Empathy has also been implicated in explanations of the nonconscious mimicry associated with the so-called “chameleon effect.” See Chartrand and Bargh (Citation1999).
[6] This avenue of investigation was suggested to me by a reviewer for this journal.
[7] A full discussion of these results is beyond the scope of this paper, but a representative sample can be viewed in Warneken and Tomasello (Citation2006). For a dissenting view, see Heyes (Citation1998).
[8] It is perhaps for this reason that theorists have been reluctant to suppose that contagious yawning might serve as a model for early infant imitative capacities. Arguing for an innate but primitive releasing mechanism for parallel behavioural modeling threatens the view that infants employ higher level representational and imitative strategies in response to particular stimuli (see, for example, Meltzoff & Moore, Citation1977, Citation1983 for versions of the higher level theory). Since yawning is best described as a syndrome of automated and automatic neurobehavioural responses, any account of infant imitation in terms of stereotyped action patterns makes little demand on innate higher-level cognitive capacities. See Provine (Citation1989a) for a discussion of yawning as a model for infant imitation.
[9] Provine (Citation2005) suggests that the gaping mouth does not have the contagion effect because it is ambiguous between yawns and other vocalizations. If this is true, then it is suggests a system for recognizing yawns that is invested in weeding out false positives. It seems that the causes of yawning contagion are determined to make sure that it is only yawns that cause yawns.
[10] This phenomenon has not been well explored, but the sound of running water is cited as a contibuting cause of urge incontinence. See Jabs and Stanton (Citation2001, p. 60).
[11] Resimulating the reflex response here would require concepts to be composed not merely of visual stimuli, but tactile ones. Both Prinz and Barsalou are committed to the idea that concepts are composed of sensory images in this broad sense.
[12] In these instances, the yawning contagion might be interpreted as an instinctive response to a perceived threat or challenge. However, in automatically reproducing the challenge—to threaten back, so to speak—a yawning reflex would appear to be unacceptably insensitive to the context in which the threatening behaviour is displayed. There are times when giving in to threats is a prudent recourse for lower status adults or juveniles. While it might be the case that yawning behaviours are suppressed in particular situations, there is no evidence to suggest that this is the case. A similar explanation does not seem palatable in the human case. Talking about threatening behaviour is quite different than having it performed in one's presence.
[13] A thermal variant of this proposal has recently been suggested by Gallup and Gallup Jr. (Citation2007). On this view, yawning serves a cooling function for the brain.
[14] My pet theory of yawning function derives from recent speculation that our evolutionary precursors breathed through their ears (Brazeau & Ahlberg, Citation2006). Yawning may be a vestigial tactic to increase air intake by stretching the eustachian tubes between the ears and our air passages to the lungs. This is, of course, highly speculative and relies on the contention that the yawning reflex would not erode after millions of years without fulfilling this function.
[15] Interestingly, some (though not all) larger herbivores (like giraffes, see Greco, 1992) do not appear to yawn—perhaps this correlates with susceptibility to predation.
[16] Clearly some animals that yawn are not active participants in social groupings. Crocodiles yawn, but they live relatively solitary lives.