"Systemisers are better at maths". But be careful of sweeping generalisations...

The title of this post - "systemisers are better at maths" - comes from the findings reported by Paola Bressan [1], an author not unfamiliar to this blog (see here). This time around, the author has opted for a topic a little less 'controversial' [2] than last time, in the form of an analysis of the 'empathising-systemising theory'. In particular, the notion that mathematics is typically a systemising activity (based on rules and laws) and so those who lean more towards being systemisers should be better at maths. That's the theory anyway...

The word 'autism' is mentioned in the Bressan paper because of the *connection* made between systemising and autism by some big names in the autism research field. As far as I can see however, the Bressan study did not include anyone diagnosed with autism or an autism spectrum disorder (ASD) but rather relied on data from mostly university students studying "mainly psychology and engineering." Said student participants (N=201) were given a couple of measures to test maths skills (including a 'how good are you at maths?' self-report measure) alongside tests for non-mathematical intelligence and 'systemising tendencies' in the form of the Italian version of the Systemising Quotient (SQ-Short).

Results: the data for the study are freely available to anyone and everyone (see here). Bressan observed a few details. So: "Systemising was predicted by sex, with men scoring on average higher than women." Occupation, I assume meaning what participants were studying, also showed a potential relationship with systemising scores too. Then to the main event: "In a sample of students of a diverse range of disciplines, the systemising score predicted both self-assessed mathematical skills (201 participants) and mathematical intelligence (151 participants). This remained true after controlling for nonmathematical intelligence, for occupation (social vs biological/physical careers), and for sex."

These are interesting results. They offer some support for the idea that cognitive style *might* be an important factor when it comes to 'success' or not in certain types of discipline, and require further study. But...

Allowing for my 'no sweeping generalisations are required' sentiments that are typically included with my analysis of research on this blog, I'm still a little reserved on this topic. I'm reserved because on the previous occasion that I've covered maths achievement and systemising (see here), the results were a little different. The paper by Escovar and colleagues [2] for example, reported that social skills seemed to be more important to maths ability. They also observed that "mathematical achievement was not related to systemizing or the discrepancy between systemizing and empathizing" in their study. Bressan criticised this study for a potential lack of statistical power, but I'm slightly less critical of those results, particularly because Escovar et al utilised a wider range of study instruments covering a wider range of potentially important variables. I'm also inclined to mention how maths ability can sometimes be clouded by other factors. Take for example another post I wrote on maths problem solving ability and autism (see here) and how issues like attention and anxiety can play a role on performance. That and also the fact that not everyone on the autism spectrum is some sort of maths genius...

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[1] Bressan P. Systemisers are better at maths. Sci Rep. 2018 Aug 2;8(1):11636.

[2] Escovar E. et al. The Empathizing-Systemizing Theory, Social Abilities, and Mathematical Achievement in Children. Sci Rep. 2016 Mar 14;6:23011.

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'Artistic creativity' and risk of hospitalisation for schizophrenia, bipolar disorder and unipolar depression

"Students of artistic subjects at university are at increased risk of developing schizophrenia, bipolar disorder and unipolar depression in adulthood."

So concluded the findings reported by James MacCabe and colleagues [1] who set about examining whether studying a creative subject at high school or university placed someone at an enhanced risk of later hospitalisation for a mental disorder such as schizophrenia, bipolar disorder or depression. The rationale behind the research was the 'long-standing idea' that "mental disorders are associated with enhanced creativity, intelligence or artistic talent."

To test the hypothesis, researchers employed some of those fabulous Scandinavian population registries (yet again), this time covering the population of Sweden. Based on the "unique registration number carried by all Swedish residents" they were able to look at educational records, results of intelligence tests (via testing during military service) and details of any psychiatric hospitalisations for nearly 4.5 millions people. A creative subject studied at high school or University was defined in both a broad sense - "which included a wider variety of creative or artistic subjects corresponding to ‘Art and Media’... but excluding ‘Science and History of Art, Music, Dance, Film and Theatre’" and also following a narrower definition: "comprising visual arts, music, dance, theatre and drama, film, radio and TV production, and fashion design." As I said, a fabulous population resource.

Results: about 5% of the population studied (~194,000) were deemed to have studied an artistically creative subject by the broad definition, falling to just over 1% (50,000) when the narrow criteria were followed. As per that opening sentence of this post, there did seem to be something in the idea that studying an artistically creative subject was *associated* with hospitalisation for schizophrenia, bipolar disorder and unipolar depression. Authors also noted that: "The associations remain when the analyses are restricted to sibling pairs, indicating that family-level factors alone cannot explain the association."

The possible reasons for this association are also explored by MacCabe et al. The ‘balancing selection’ hypothesis is mentioned whereby "the genetic variants conferring risk for psychosis also carry a biological advantage, such as enhanced intelligence or creativity, and this translates into reproductive advantage in the relatives of those with psychoses; thus maintaining the frequency of risk alleles in the population." Similar to the idea that the genetics of autism are probably not just 'genes for autism' (see here) so the genetics potentially linked to psychiatric disorders such as schizophrenia, probably also affect other areas of functioning (positively and negatively). Authors also entertain more 'psychological theory' (here we go) where, for example: "certain cognitive styles may be associated with artistic creativity and psychosis." Personally, I'd be more inclined to believe the first explanation over the second on the basis that 'cognitive styles' tends to make rather sweeping generalisations (see here for an example) and are rather difficult to confirm/refute from a scientific perspective.

Despite the results obtained by MacCabe, I am not totally convinced of any universally general connection between artistic creativity (or any other kind of creativity) and psychiatric disorder. I say this on the basis of other, independent findings (see here) that have not been so kind to the hypothesis. I'm also a little cautious that making such sweeping generalisations could potentially detract from the often very significant effects that such psychiatric disorders have on a person's life; many of which can lead to issues such as 'hospitalisation' (where hospital records were an important data source for the authors in this study).

Still, these are interesting results and have grabbed some media attention...

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[1] MacCabe JH. et al. Artistic creativity and risk for schizophrenia, bipolar disorder and unipolar depression: a Swedish population-based case–control study and sib-pair analysis. British Journal of Psychiatry. 2018. April 26.

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