Saturday, January 26, 2013

Doodling and the default network of the brain : The Lancet

Doodling and the default network of the brain

What does the brain do when we day dream, our mind wanders, our thoughts flit from one thing to another, or we seem to be mentally "idling"? Some evidence has accumulated during the past 30 years that implicates the involvement of an intrinsic default network in the brain: an anatomically defined network which includes the medial temporal lobe and medial prefrontal subsystems and posterior cingulate cortex. Functionally, this network supports a baseline, so-called default, mode of cortical activity that engages when externally directed thought is absent (stimulus-independent thought) and also possibly during watchfulness towards the external environment (stimulus-orientated thought). Brain activity in this default system seems to be inversely related to activity in another intrinsic network, the "attention system", which is activated during goal-directed cognition. These networks have been explored mainly using brain imaging, but—though at first sight incongruous—could doodles, and the doodling that produces them, provide another way of probing the default network and the brain functions it supports? Although of enduring interest to the public and to teachers, psychologists, psychiatrists, and many in the humanities, doodles have received little attention from neuroscientists. Because of the circumstances in which they are often produced, however, doodles and doodling might reveal insights about how the brain functions, notably when in "idling" mode.

Everyone will have seen a doodle and very many people will themselves have made such drawings. However, no doodler sets out in advance to doodle, and doodlers are individualistic and do not seem to copy one another. Although doodling has a history dating centuries, its prevalence is unknown. Judging from David Greenberg's Presidential Doodles, at least 26 of the 44 American Presidents doodled, which suggests the practice is fairly common. The Oxford English Dictionary defines the doodle as "An aimless scrawl made by a person while his mind is more or less otherwise applied." This definition presents a difficulty: other than perhaps for the individual draughtsman at the time, the prevailing state of mind of the doodler is almost always unknown. This caveat applies to everyday doodling, but especially to the corpus of historical doodles. These range from those made by such illustrious figures as Albrecht Dürer, Desiderius Erasmus, and Fyodor Dostoyevsky (figure) to the anonymous 16th-century town clerks of Antwerp and 18th-century ledger-clerks of the Banco di Napoli, whose doodles so intrigued the art historian Ernst Gombrich in his magisterial study of doodling. In practice, therefore, it is the nature and form of the drawing, and especially its context, that identify a doodle.

Doodles on a page from Fyodor Dostoyevsky's manuscript of The Devils

Reproduced with permission of RIA Novosti.

Much of the lay and scientific literature on the subject has been devoted to interpretation of the doodle, and is based on the unsubstantiated premise that the doodle provides a window into the personality and psychology of the doodler. Even children's doodles have received not only pedagogical but also lay attention, exemplified by the newspaper article offering to reveal "what your doodle says about you". The interpretation usually varies according to the discipline making that interpretation. For instance, schoolteachers have sometimes interpreted children's doodles in terms of attention span and learning, whereas some psychologists have tended to interpret doodles in terms of their patients' underlying personality and psychological traits. Such interpretations merge seamlessly with those relating to doodles drawn by patients with psychiatric disorders, including schizophrenia. Furthermore, some doodles resemble drawings made under the influence of mescaline, and others recall surrealist automatic drawing. While such views are necessarily subjective, a few researchers have attempted a more objective analysis.

Surely one of the most extensive investigations of doodles was a 1938 study by W S Maclay, E Guttmann, and W Mayer-Gross who assessed 9000 doodles sent in by the public in response to a competition run in 1937 by the Evening Standard newspaper, which had offered a prize for doodles published and analysed by a psychologist. The authors found that doodles were produced during states of idleness, boredom, leisure, meditation, and "affective tension"—indecision, concentration, expectation, and impatience. But when an individual doodles, the brain may also be highly creative, being occupied, for example, in solving mathematical problems, or generating ideas for new works in literature, art, or design. For some doodlers, therefore, doodling may be crucial for creativity, whereas for those at the other end of the spectrum, doodling seems to be relaxing or simply entertaining.

The final graphic expression reflecting apparently several disparate cognitive states, doodling is a motor act, and when occurring under conditions such as impatience, boredom, and indecision, it seems to alleviate those conditions. This effect recalls other stress-alleviating motor activities such as fidgeting, scratching, and fiddling with different objects, in the same way that non-motor activities, for example playing background music, can appear calming and sometimes aid concentration and creativity. What are the subconscious or semiconscious cognitive processes that give rise to the doodler's graphic compositions? Interpreting or analysing any particular doodle seems to have little merit. More fruitful perhaps is considering whether doodling indeed reflects some functions of the brain, whether in "wandering" mode and perhaps engaged with internally generated thoughts, or during watchfulness towards the environment.

As already acknowledged, investigation is hampered by the very circumstance in which typical doodling occurs: the individual's focused attention is by definition partly or completely elsewhere, a problem that has engaged neuroscientists too when investigating the default network. An attempt to surmount this difficulty was made by psychologist Jackie Andrade who devised a surrogate doodling test. Healthy volunteers listened to a monotonous recorded telephone message and were asked to monitor the names of people coming to a party. Half the volunteers were asked to undertake a repetitive pencil-and-paper shading task at the same time. Those in the "doodling" group performed better on the auditory monitoring task, and on a subsequent memory test. Why? In some circumstances in which doodling occurs there is increased arousal. These circumstances include not only the various forms of "affective attention" noted by Maclay and colleagues and which now might be called stress, but, perhaps counterintuitively, probably also boredom and its frequent accompaniment, day dreaming. Creative thoughts and problem-solving, too, are surely associated with arousal? In other circumstances, the individual is not only aroused but likely to have increased watchfulness to surrounding events. Among other factors, Andrade postulated that doodling might stabilise arousal at an optimal level, "keeping people awake or reducing the high levels of autonomic arousal often associated with boredom", and also more particularly that doodling might aid concentration by reducing day dreaming.

Thus there seem to be certain parallels between doodling and brain activity in the default network: doodling appears to be most commonly undertaken when stimulus-independent thought is occurring, as when day dreaming or mind-wandering, and less commonly also during stimulus-orientated thought such as watchfulness. Both these circumstances are the very circumstances in which the brain's default network, and perhaps arousal, are implicated. But whatever brain processes are enlisted during doodling must also be well-established, because an individual's doodles usually have a consistent form: those who draw geometrical patterns, or faces, or scenes, often seem to do so habitually, and many doodlers have themselves commented on the stereotyped nature of their drawings made over many years. These features suggest that the underlying cerebral processes are both specific to that individual and stable over the long term. However there is also variability. This is seen in the differing extent to which people doodle, and some individuals never doodle. Similarly, the propensity to engage in mind-wandering and similar cognitive processes, and to engage the default network, varies too, and whether doodlers and non-doodlers might engage the default network differently remains unknown.

An intriguing form of illustration, doodles may prove to be a unique and hitherto untapped resource for investigating certain aspects of brain function, and functional imaging studies of surrogate doodling, imagining doodling, and perhaps serendipitously even during doodling itself might provide new insights into the wandering mind in particular. And providing pencil and paper to the anxious, the distressed, and the disturbed might even have unexpected therapeutic benefits.

I am most grateful to Dr J Schott for helpful discussion about this essay.