The remote diagnosing of psychiatric and behavioural disorders is a particular bugbear of mine. It's something that autism research and practice in particular has had to endure for quite a few years, as a volley of historical figures for example, were revealed to be supposedly autistic. Such musings also add a temporal aspect to proceedings.
The paper published by Penny Spikins and colleagues  takes such temporal armchair diagnosing to the absolute max, with their contribution to the "long standing debate about the existence of ‘autistic traits’ in European Upper Palaeolithic art." Some of the media that followed these findings really went to town, as per headlines such as 'Ice Age cave artists were AUTISTIC' (capital letters were already included in the headline, not added by me - see above) and 'Autism shaped the art of survival'. Wow. All of that information from a few paintings and carvings...
So how did the the authors and the lay media arrive at such a conclusion?
Well, first and foremost Spikins et al did not say that the makers of such early art were 'autistic'. They focused on autistic traits, and in particular the idea of an "extreme local processing bias" or attention to detail trait that seems to accompany the diagnosis of autism (for some). Importantly, they note that: "Local processing bias is common in autism but also seen in individuals without autism" and "‘Autistic traits’ in Upper Palaeolithic art do not necessarily signify the work of an individual with autism." So, from the outset, we can probably do away with that rather sweeping [diagnostic evidence-free] media headline on Ice Age cave artists being autistic.
Quite a lot of the Spikins paper focuses on what's been observed - directly observed - in some of those diagnosed as being on the autism spectrum when it comes to artistic talent, which is then 'extrapolated' to such prehistoric artists. This includes some rather nice pictures drawn by individuals with autism who expressed a "marked local processing bias" compared with age-matched drawings from non-autistic individuals. We're also told that the use of the (very) famous 'are you autistic?' self-report screener that is the Autism Spectrum Quotient (AQ) by the authors, revealed that "individuals with a very high autism quotient (AQ) of 32 or above, which is taken as indicative of an autism spectrum condition within a population sample were statistically much more likely than neurotypical individuals (i.e. those with a lower AQ score) to have an interest in and experience of art outside of any school curriculum." 'Indicative of an autism spectrum condition'? Well, we'll see. And I still have some problems with what comes under the term 'neurotypical' too (see here).
Of course you can perhaps see the issue here. Take one block of 'evidence', some of it based on individual case reports and some of it based on an 'autism' screener that probably picks up an awful lot more than 'just autism' (see here and see here and see here for examples), correlate and correlate some more and hey presto, we reach the conclusion that the art must have been drawn by someone expressing an autistic trait or even someone who was autistic.
A testable hypothesis? No, it's not. We don't know who drew those paintings or made those carvings. We don't know anything about them personally and we certainly don't have any evidence about whether they expressed any significant autistic or any other kind of trait. For all we know, the paintings or carvings could also have been made by more than one person; a family or group effort if you like. We just don't know because, well, those artistic depictions were made thousands and thousands of years ago before the tools that help us record history were even a twinkle in the cosmic eye.
I don't want to come across as poo-pooing such 'observations' stressing how autistic traits are not necessarily a new thing because, in essence, I do think that some autistic traits have probably been with us from our earliest evolutionary times (see here). I say that on the basis that the traits of autism are not some 'magical' behaviours that are completely distant from the human experience; more likely they represent the extremes of what is typically seen in the general population at particular ages and stages and environments. Taking such logic back in an evolutionary sense, one can for example see how something like an 'attention to detail' could be a good survival skill if your life depended on it.
But I do think one has to be very, very cautious about such research and any 'feelgood' factor it might attempt to generate or put forward. Autism, as a clinical definition, only really came about in the last hundred years or so, and for many, any benefits derived from a 'marked local processing bias' have to be balanced with the possible downsides to such directed focus (e.g. increased rumination and anxiety). I'd also add in that the idea that Palaeolithic Art (or indeed, any kind of art) merely comes about as a result of traits that are noted in the context of psychopathology is a pretty dangerous path to take. It risks boiling down human efforts such as creativity and artistic skill to nothing more than diagnostic characteristics and feeds into narratives such as the "creativity is akin to insanity" headlines of not so long ago (see here). As I've said before, people are so much more than the labels they've received or the diagnostic term they identify with.
In short, Palaeolithic art is interesting and adds to our understanding of how we evolved. But it simply cannot provide an accurate window on any states and traits of those who created it...
To close, there's a wedding on today apparently. Best wishes to the happy couple. And not to make light of our Royal Family, but The Windsors TV show is absolute comedy gold (particularly Harry Enfield)...
 Spikins P. et al. How Do We Explain ‛Autistic Traits’ in European Upper Palaeolithic Art? Open Archaeology. 2018; 4: 262-279.