After millennia spent migrating across the globe in primitive hunter-gatherer groups, ancient humans began forming permanent settlements during the Upper Paleolithic, about 50,000 to 11,000 years ago. This period of percolating civilization is characterized by the adoption of complex tools, the invention of agriculture and animal domestication, and an explosion of highly realistic art that is quite different from the simple and symbolic doodlings that preceded it.
What drove the evolution of Ice Age art has long been debated by archaeologists and anthropologists, though all agree that the change marked a shift in human cognition toward “higher order consciousness”.
One of the leading theories is that our curious ancestors began ingesting hallucinogenic compounds on the regular, and the resulting trips inspired new forms of expression. But in the late 1990s, researchers began noticing that elements of some of the most famous Upper Paleolithic art – European cave paintings – are very similar to art produced by individuals with autism spectrum disorder (ASD). This led to the highly controversial counter theory that nascent European societies not only tolerated members with what we would define as neurologically atypical traits, but supported them as they fulfilled the non-essential role of clan artist.
Now, researchers from the University of York argue that the current scientific literature actually refutes the idea that ancient cave painters were high on psychedelics, and indicates instead that many harbored an obsessive cognitive trait closely associated with ASD called “detail focus”.
"We looked at the evidence from studies attempting to identify a link between artistic talent and drug use, and found that drugs can only serve to disinhibit individuals with a pre-existing ability,” said Professor Penny Spikins, first author of the paper published in Open Archaeology.
“The idea that people with a high degree of detail focus, many of which may have had autism, set a trend for extreme realism in Ice Age art is a more convincing explanation."

According to Spikins and her colleagues, though taking mind-altering drugs may have changed our perceptions, it cannot explain how humans suddenly developed the technical capacity for realistic depiction.
“Drugs may influence motivations, and spur artistic production, however they do not make us talented artists (except perhaps in our own estimation),” they wrote in their paper.
A number of past psychological investigations into the basis of exceptional natural artistic talent have found that the presence or absence of detail focus, also known as local processing bias, determines whether an individual will be able to accurately recreate the features of objects and scenes they observe. Though this trait is not limited to individuals with ASD, it also appears to be genetic.
The authors conclude that the gene variations underlying detail focus and several forms of non-intellectually disabling ASD – boosted concentration, pattern recognition, and enhanced sensory processing – were likely already present in Ice Age humans. Yet instead of being selected against, the causative sequences spread through populations because those with them contributed significantly to our success as a species.
"As well as contributing to early culture, people with the attention to detail needed to paint realistic art would also have had the focus to create complex tools from materials such as bone, rock, and wood," Spikins said. "These skills became increasingly important in enabling us to adapt to the harsh environments we encountered in Europe."