How many different uses can you think of for an umbrella in 1 minute?
Questions like this are used to assess so-called divergent thinking, which is arguably one of the most important aspects of creativity from a cognitive point of view.
Of course, creativity, like beauty, lies in the eye of the beholder, and according to the 19th century French writer, Isidore Ducasse (aka Comte de Lautréamont, 1846–1870), the chance encounter of an umbrella and a sewing machine on a dissecting table is beautiful. But it is also creative to the extent that this odd conjunction of objects famously anticipated the aesthetic of the surrealists, who quickly claimed Ducasse as a prophet of the movement. Before long, dog combs, bottle-racks, and even a urinal were being exhibited. This was not just new uses for everyday objects—the urinal became a "fountain"—but divergent thinking epitomized as art!
Now a remarkable new study using brain-imaging suggests that, to the extent that creativity is indeed based on divergent thinking, it is a product of a brain which can think outside the box because the box itself is leaky.
Psychometrically-measured creativity can be correlated with thalamic dopamine receptor densities in the brain. As the authors of the study point out, divergent thinking is influenced by dopaminergic function, and in particular by the A1 D2 dopamine receptor gene. And as they also observe, this polymorphism is unrelated to general intelligence, suggesting that the long-term storage and retrieval of information on which divergent thinking depends is an independent cognitive function.
The new study focuses on two regions in particular: the thalamus and striatum. Previous studies have shown that the thalamus (a central hub of brain connectivity) contains high levels of D2 receptors and that thalamic D2 receptor densities are reduced in un-medicated schizophrenics and that this is negatively related to severity of a broad range of symptoms. In accordance with existing findings, the researchers argue that reduced D2 receptor-density in the thalamus lowers gating thresholds, which in turn results in reduced filtering and regulation of information flowing through it—the leaky box effect, if you like.
Additionally, they suggest that this increases excitation of the prefrontal cortex, which is known to be active in divergent thinking tasks. As the authors put it, “A decreased signal-to-noise ratio in thalamus would decrease information gating and possibly increase fluency; decreased signal-to-noise ratio in cortical regions should better enable flexibility and switching between representations; similarly, the associative range should be widened and selectivity should be decreased which might spur originality and elaboration,” producing what the authors call “creative bias.”
The researchers also point out that the networks relevant to divergent thinking overlap with those affected in schizophrenia and bipolar disorder and that D2 receptors have been linked to psychotic symptoms. They add that “the creative bias may also bring a risk of excessive excitatory signals from the thalamus overwhelming cortical neurotransmission, with ensuing cognitive disorganization and positive symptoms.”
This is exactly the kind of thing that you would expect if you took the concept of hyper-mentalism seriously and saw such effects as evidence of hyper-mentalizing at the level of brain function. According to the diametric model of the mind, divergent thinking should indeed be enhanced in psychotics—at least to the extent that you could see delusions as thinking that was divergent to a pathological degree and therefore as a form of hyper-mentalism.
The diametric model also opposes autism to psychosis and suggests that autistics might be the opposite: non-divergent to the point of pathological single-mindedness and mental rigidity. This certainly seems to fit their often-reported insistence on sameness, repetition, and over-focused attention on a single issue or interest.
However, outstanding creativity is also sometimes associated with autism, as authorities like Michael Fitzgerald and Ioan James have shown, so we clearly need to be careful about jumping to conclusions. Andy Warhol, for example, is diagnosed as an Asperger’s case by both, and his pop art images of soup cans and other everyday images might easily be seen as pictorial representations of divergent thinking.
Nevertheless, to the extent that the brain mechanisms underlying delusions might be predicted to be reduced or absent in autistics as the diametric model definitely suggests, we might also argue that creativity in autistics might rely less on a leaky thalamic box and more on an ability not to be boxed in by the convergent thinking of other people. This would certainly be concordant with the hypo-mentalism of the disorder, and probably based on quite different brain mechanisms from those explored in this study.
Perhaps the researchers might include autistics next time, as I have suggested before in relation to similar findings. At the very least, this would help to explore the mystery of creativity, and at best might prove yet another acid test of the diametric model of the mind.
(With thanks and acknowledgments to Ahmad Abu-Akel for bringing this publication to my notice.)
