Consciousness, Literature and the Arts

Archive

Volume 12 Number 1, April 2011

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Work versus Play: What recent brain research can tell us about play, theatre, and the arts, and why it is taking scientists such an unconscionably long time to realize their importance

by

Charles Whitehead

 Three modes of social display

 There is a pen on my desk. I could use it to write with. I could use it to stir my coffee. Or I could play with it.

If you saw me pretending that my pen is an aeroplane, how long do you think it would take you to figure out what I am doing?

You might realise I am playing from my facial expression. The so-called “play face” – with raised eyebrows and covered teeth – says “I am not going to bite you.” Mothers use it when they pretend to be The Monster, and their toddlers flee squealing with terrified delight. The same facial expression is used by chimpanzees to signal the difference between a play fight and a real fight (Young 1992). Mock aggression is common among primates and social carnivores, and is an important part of socialization. This expression of non-aggression comes to be used to indicate all kinds of play – in this case, pretending that a pen is an aeroplane.

Secondly, you could understand that I am using the pen as a toy aeroplane because I make it move like an aeroplane. I may also use my voice to mimic aeroplane noises. Representation by resemblance is known as “mimesis”.

It takes an average adult less than three seconds to recognise a pretend action of this kind.¹ So, understanding a mimetic representation of an aeroplane is pretty easy for us humans. But now consider a more difficult task. Imagine you are playing charades, and you want to convey the title of this chapter using mimetic representation.

For the first word “work” you might mime someone digging. Your audience will start to guess – do you mean “digging”? Or “spade”? So you then mime someone hammering a nail. You might have to mime three or four different kinds of work before people realise that you intend an abstracted general term such as “job” or “task”, and it may take even longer to get to the precise word “work”. When your audience finally gets it right, you indicate their success by nodding to say “yes” – which is not a mimetic signal at all, but a conventional cryptic gesture.

Next comes the word “versus”. You might decide this is too difficult and move on to “play” – indicating “third word” with a combination of conventional mimetic and cryptic gestures agreed upon by people who play charades. The word “play”, of course, presents the same difficulties as the word “work”. You might have to mime several specific instances of play before they get the right word. And if you are finding all this a bit laborious, just wait till you get to the twenty-fifth word: “unconscionably”. Abstract concepts are at best difficult to convey using mimesis, whilst the relational and syntactical meanings of words like “versus”, “and”, “the”, and “is”, are virtually impossible.

So, what I hope I have shown is, firstly, that you can easily infer someone’s playful intentions from their facial expression and body language. This is an example of gesture-call communication, which also includes vocalizations such as laughing and crying. Unlike mimesis, gesture-calls are largely involuntary. Implicit displays of this sort signal emotions, desires, and even autonomic states – such as yawning when you feel tired.

Secondly, mimesis is also easy to understand if all you want to convey is a specific concrete idea like “aeroplane”.  

But – thirdly – if you try to force mimesis to do the same job as language then there are enormous difficulties. Language is a conventional cryptic code – it refers to things, thoughts, perceptions and ideas by consensual agreement and not by resemblance. Cryptic codes include language, mathematical denotations, traffic signals, and nodding your head to say “yes”.

So we have at least three distinct modes of social display (Burling 1993) which express three distinct levels of subjective experience. What social displays do is project experiences outside the body into a public space where anyone can see, touch, or hear them. This makes subjective states objective. It makes them salient so that we begin to notice that we and others have such states – and so become self-conscious and other-conscious (Whitehead 2001).

Implicit displays make affective and autonomic states public; mimetic displays make perceptions and concrete ideas public, and cryptic codes make abstract, generalized, and syntactical ideas public. According to social mirror theory, we humans are so highly self-conscious and other-conscious because of our formidable armamentarium of social displays, which extend far beyond mere communication, and include all forms of play and performance, including all the cultural arts (Whitehead 2001, 2003, 2006). Figure 1

Imaging studies of pretend play

We² took the idea that you can use a pen to write with, or to stir your coffee, or as a toy aeroplane, as the basis of a brain-mapping experiment on pretend play (Marchant et al. in preparation). We used eighteen familiar household objects, and prepared video sequences showing an actor using each object in three ways – the normal way, an unusual way, and a pretend way.

A subsequent literature search revealed only one published study of pretend play – which also used action videos (German et al. 2004). Previously, we³ had done a pilot study of role-play (Craik et al. 2000). So, to my knowledge, there have only been three imaging studies of pretend play.

The two studies of observing pretence produced very similar results. Both these studies involved people watching video clips of actors pretending to do something, contrasted with videos of actors doing non-pretend, instrumental actions – that is, brain activity associated with observing non-pretend actions was subtracted from brain activity associated with observing pretence.

The role-play study produced different results. Here, participants were not observing play, but actually performing, in imagination, roles taken from Hamlet and Macbeth.

Figure 1 is a simplified diagram summarizing the main results of all three studies. The first point to note here is that the temperoparietal and temporal areas activated by observing pretence, and the medial prefrontal areas activated by pretence and role-play, are well established as the “theory of mind” (“ToM”) network (Frith & Frith 1999, 2000, 2001).

“ToM” is shorthand for the ability to interpret other people’s behaviour – and your own behaviour – in terms of mental states (Baron-Cohen 1995). The term usually refers to epistemological mental states – such as knowing, believing, pretending, imagining, dreaming, etc. In other words, this is a particular level of self- and other-awareness, as distinct from the level of emotion and desire.

German and colleagues (2004) took this to mean that theory of mind is automatically engaged whenever people observe pretence. However, according to social mirror theory (Whitehead 2001, 2003, 2006; cf. Lillard 2002), the explanation is the other way round – that is, pretend play is necessary for the development of ToM, and ToM engages brain structures dedicated to pretend play.

Secondly, all the areas activated by pretence and role-play coincide with areas regularly implicated in story-telling or narrative, regardless of whether a story is told in words or pictures (Mar 2004). That is, the theory of mind network, together with the inferior parietal lobule, dorsolateral prefrontal cortex, opercular prefrontal cortex, and the posterior cingulate and precuneus, have all been implicated in studies of narrative.

So ToM – theory of mind – uses a subset of the brain areas implicated in two studies of pretend play, and pretend play utilizes a subset of the areas required for story-telling. We² find it implausible that role-play would not involve major ToM areas in the temporal lobes. The fact that our earlier study of role-play did not show this, we think, implies that there was something wrong with our³ selection of control tasks. If we are right, then story-telling involves the same or very similar brain areas to role-play. These results suggest that pretend play during childhood scaffolds both the development of role-play and ToM, and that the ability to understand and enjoy stories involves pretend play generally, including role-play.

Thirdly, all the activations you see in this slide involve the most expanded portions of human neocortex (Whitehead 2003, 2006). The average human brain is around three times larger than the average chimp brain, and this reflects two periods of brain expansion during human evolution. But not all structures are equally expanded. Primary areas – such as primary visual, primary motor, and somatosensory areas – are the same size in humans and chimps, because they do the same kind of job. Secondary areas are two to three times larger in humans relative to chimps. But the most massive expansions occurred in multimodal integration areas. The prefrontal lobe is about six times larger than a chimp’s, and the temporal lobe, especially the pole, is also much larger, though I don’t have a figure for this. The inferior parietal lobule might be described as “infinitely expanded”, because there is no unequivocal homologue in the chimpanzee brain.

Fourthly, all the areas implicated by pretend play, role-play, and narrative – with the exception of the dorsolateral and opercular frontal areas – are also commonly reported as so-called “deactivation areas”. Cognitive neuroscientists have repeatedly observed that these areas are more active during periods of supposed rest than they are during laboratory tasks used to investigate cognitive processes (Iacoboni et al. 2004). So researchers began to wonder what people were doing when they were not supposed to be doing anything. Some authors proposed that this resting brain activity was a “default state” of the human brain. When we see that these areas coincide with activations associated with narrative, then it seems likely that people are telling themselves stories during their idle moments – in other words, daydreaming.

The human brain has the extraordinary ability to run social scenarios in imagination, with a cast of actors – toy people – who behave as though they have minds, knowledge, beliefs, desires, and emotions of their own. I call this “theatre of mind”. The implication is that the human brain can run multiple minds in parallel, and when this process goes wrong, you get multiple personality disorder (cf. Hilgard et al. 1975; Bliss, 1986; Brown, 1991; Mitchell, 1994; Whitehead 2001).

Imaging studies of tool-use and object manipulation

The industrial revolution and the protestant work ethic (Weber 1904-5) have created a world in which work is valued over play (Turner 1982),  object over social skills (Smith 1988), logic over make-believe (Jennings 1990), and science and technology over the arts (ibid). Educators know that play is necessary to healthy childhood development – but still see it as essentially a waste of time, and believe that the sooner children start “working” the better (cf. OFSTED 1999). When archaeologists try to understand the evolution of the human brain, they look at stone tools, and wonder why technological changes do not correlate with brain expansion (cf. Mellars & Stringer 1989). When neuroscientists look at the brain, they think they have to study “work”,  so we have more than thirty imaging studies of tool-use and object manipulation (Grèzes & Decety 2001), as against only three studies of pretend play.

Many of these tool-use studies followed from the discovery of “mirror neurones” in macaques (Gallese et al. 1996; Rizzolatti et al. 1996). Rizzolatti and colleagues noticed that when a monkey performed “simple goal-directed motor actions, such as…grasping for a toy or a piece of food” (Rizzolatti et al. 2006), certain neurones in the brain fired. To their surprise, they subsequently noticed that the same neurones fired when the monkey saw a human experimenter or another monkey perform the same action. They called these “mirror neurones”, and recently published a popular science article called “Mirrors in the Mind” (ibid). Now you would expect that, having discovered mirror neurones, the first thing that should have occurred to them is the likely relevance of social mirror theory, which holds that “mirrors in the mind depend on mirrors in society” (Whitehead, 2001), and which in fact tacitly implies the existence of mirror networks in the brain. But they didn’t think of this because their research was focussed on goal directed instrumental actions – that is, work rather than play.

Since then there have been many studies of tool-use and object manipulation, intended to investigate mirror systems in human brains. Figure 2 plots major centres of brain activity from nine such studies.⁴

Clearly, there are major differences between tool-use and pretend play. Brain activity associated with work-like tasks is almost entirely in the left hemisphere, whereas play involves much more right-hemisphere activity. Secondly, there is a good deal of motor activity, mainly associated with executing rather than planning or observing actions. Thirdly, there is a cluster of superior parietal activations, again mainly linked to execution. This area of the brain is involved with navigational body movements. Fourthly, there is very little medial brain activity; and finally, very little prefrontal involvement other than a large cluster of activations in the left frontal operculum. Pretend play also involves this area, though in both hemispheres rather than just the left. It includes Broca’s area, classically linked to motor sequencing for speech – but it would seem that the area is responsible for more than one kind of motor sequencing, including grasping objects, playing with toys, role-play, and listening to stories – even after the effects of language have been subtracted out.

Imaging studies of dance

The left hemisphere pattern of activity associated with tool-use is remarkably similar to that associated with dance (Figure 3). Dance involves a great deal of activity in the opercular frontal area, a scatter of motor activations, and a further cluster in the superior parietal lobule. There is very little prefrontal activity other than in the operculum. What is different about dance is that there is far more right hemisphere involvement, and also more medial activity – notably in the posterior cingulate and precuneus – an area that we have associated with narrative, role-play, and daydreaming. Other areas common to dance, pretend play, and narrative are the superior temporal sulcus and inferior parietal lobule.

There have been only four imaging studies of dance, and three of them (Calvo-Merino et al. 2005, 2006; Cross et al. 2006) were not intended to be studies of dance per se, but were simply using dance as an alternative to tool-use for investigating mirror systems. Specifically, the authors wanted to check whether knowing how to do something affected the way you perceived others doing it. When dancers watch a dance form in which they have personal expertise, it appears, certain brain areas are more activated than when they watch a form that is not familiar to them.

The lack of interest in the brain basis of dance is particularly odd when you consider that entire research departments have been dedicated to imaging studies of music, and there is a considerable volume of neuroscientific literature relating to performing and listening to music – mainly classical. Highly talented composers of classical music in the west are regarded as “geniuses”, whereas highly talented choreographers and non-classical composers are not, so this bias seems to reflect the politics of prestige in western culture.

Only two of the four studies (Brown et al. 2006 and Cross et al., 2006) contrasted dance tasks against a resting baseline, and only one (Cross et al. 2006) gives a map of this contrast (Figure 4).

Evolution of the brain and self-consciousness

The most significant activations in Figure 4 are all in areas that were expanded during the first phase of hominid brain expansion, between 2.5 and 2 million years ago (Whitehead 2003, 2006). The only gap in these findings is an apparent lack of inferior parietal activity. A prominent inferior parietal lobule first appears during this period of expansion (Tobias 1987), and you would expect far more inferior parietal activity, at least in the performance of dance. When you are dancing with other people there is an obvious need for visual, auditory, somatosensory, and motor integration – which implicates the inferior parietal lobule. However, only one of the four studies involved actual dance performance (Brown et al. 2006), and this did not involve any visual feedback. The other three studies involved watching silent videos of dance, so there was no auditory feedback.

The finding that tool-use appears to engage brain areas in common with dance is also of palaeoanthropological interest. The first unequivocal napped stone tools appear in the archaeological record around 2.7 million years ago (Bilsborough 1992: 136-7), just before the first period of major brain expansion.

These tools do not necessarily indicate uniquely human cognitive abilities (Wynn & McGrew, 1989) – orang-utans can learn to make and use similar tools (Wright 1972), and the bonobo chimp Kanzi even invented new ways of making them (Toth et al. 1993). What is more significant is that the tools were used for butchering meat. When chimpanzees capture an animal they tear it apart and eat it in a general mêlée (Teleki 1973, 1981; Strum 1981). They are grabbing their share before the others eat it. Apes cannot afford the luxury of butchering meat because they cannot trust each other to share such a valuable resource. Butchering by these early hominids indicates very high levels of social trust – unprecedented in non-human apes.

The second significant fact is that the earliest butchery sites are all riverside sites. If you are a prey animal, the last thing you are likely to do is linger near fresh water, where dangerous predators come to drink. Still less would you sit around napping stone tools and butchering meat, giving off an alluring smell that could travel a long way downwind. The only hominids we know of at that time were diminutive creatures little more than three feet tall. Yet they apparently had no fear of dangerous social carnivores such as lions and hyenas.

The only plausible explanation for these two facts – unprecedented levels of social trust, and the ability to drive off social carnivores much larger than themselves – is song-and-dance display. I presented the archaeological, fossil, and primatological evidence for this claim in a previous paper (Whitehead 2006), and have no space to repeat it here. The imaging research I have just shown you is consistent with the possibility that song-and-dance display drove the first phase of hominid brain expansion.

It also seems likely that song-and-dance display would create the necessary preconditions for the later emergence of sophisticated mimetic displays – social trust, social insight, and voluntary control over display behaviours (Whiten 1993). Dance may also have pre-adapted the brain for mimetic displays such as iconic signals, mime, pretend play, and role-play. If we go back to Figure 1, we would expect song-and-dance to lead to expansions of inferior parietal and opercular prefrontal areas, and possibly superior temporal areas and the posterior cingulate gyrus and precuneus, which are also implicated in pretend play and role-play. Whilst fossil crania show no clear evidence of prefrontal expansion across the first phase of accelerated changes in the brain – other than the opercular prefrontal area implicated in dance – it is possible that some expansion of ventromedial prefrontal cortex could have occurred. This is a grooming centre – it is involved in feelings of empathy, and response to pleasurable bodily contact, pleasant words and harmonious as opposed to discordant music. The functions of dance include grooming and entrainment (Whitehead 2001, 2003).

However, the major expansion of the prefrontal lobe – which gives us humans our vertical forehead and “highbrow” appearance – did not occur until the second phase of hominid brain expansion. This coincided with the first archaeological evidence for new forms of display – the use of red pigment, collections of attractive objects, and possibly the world’s oldest doll, the Berekhat Ram figurine, which is over 230,000 years old. It seems likely that frontal lobe expansion was associated with increasingly sophisticated pretend play, although this period also saw the descent of the human larynx to create a large tuneable pharynx, suggesting melodic elaboration of song (Whitehead 2006).

Conclusion

All the evidence I have presented is consistent with social mirror theory and a “play and display” hypothesis of brain expansion. According to social mirror theory, different modes of display create different levels of self-consciousness and social insight. Implicit displays such as song-and-dance lead to insight at the level of emotion, desire, and relationships. They are the basis of empathy. Mimetic displays such as pretend play lead to insight at the level of epistemological mental states – that is, theory of mind and theatre of mind. Such displays are part of our biological heritage, and they are the foundations on which conventional displays are built – ritual, language, music, and wealth displays – which characterise and constitute modern human culture.

However, our ancestors achieved modern-type culture at a price. Conventional displays do not simply create a new mode of self- and other-consciousness. They also produce a kind of unconsciousness. It is the job of culture to confuse us about our true biologically-given nature. That was the only way that our social but selfish ancestors could be coerced into collaborating in an unselfish system.

The result is collective deception. Collective deceptions in western science include physicalism, individualism, cognocentrism, logocentrism, genocentrism – and the cultural materialism of the west, which regards work as the opposite of play, and play as basically a waste of time. It is the obfuscatory nature of our culture that prevents behavioural scientists from recognising the importance of social displays such as dance and pretend play.

In the psychological literature, there are recurring admissions of difficulty in defining play. Authors often resort at some point to the phrase “just for fun” – in quotes because they are embarrassed to be reduced to using folk terminology. There is no scientific definition of “fun” – yet it is surely self-evident that when we are having fun, that is when we are being most true to our biologically given nature, and when the brain and the body are doing their natural work. Yet cognitive neuroscientists think they have to investigate all the things that are not fun, creating a fictitious functional anatomy of the brain. It is high time we saw more research on the displays that make us most truly human.

Notes

1.        Based on response times of eleven adults watching video clips of three different pretend actions, prior to designing a pretend play study using similar videotaped actions (Marchant et al. in preparation).

2.        The research team comprised two neuroscientists – Jen Marchant and Chris Frith – and two social anthropologists – David Craik and Charles Whitehead.

3.        The role-play research team comprised Robert Turner (principal of the functional imaging laboratory, Wellcome Centre for Imaging Neuroscience, at the time), David Craik, and Charles Whitehead.

4.        Martin et al. 1996; Choi et al. 2001; Inoui et al. 2001; Ohgami et al. 2004; Johnson-Frey et al. 2005; Fridman et al. 2006; Kan et al. 2006; Lotze et al. 2006; Naito et al. 2006.

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