Prehistoric cave dwellers living in Europe purposefully starved themselves of oxygen to hallucinate while creating their decorative wall paintings, a groundbreaking new study has found.
Researchers have been questioning for years why so many of the world's oldest paintings were located in often pitch-black tunnel systems, far away from cave entrances.
But a recent study by Tel Aviv University now reveals that the location was deliberate because it induced oxygen deprivation and caused cavemen to experience a state called hypoxia.
Hypoxia can bring about symptoms including shortness of breath, headaches, confusion, and rapid heartbeat, which can lead to feelings of euphoria, near-death experiences, and out-of-body sensations. The team of researchers believes it would have been "very similar to when you are taking drugs", the Times reported.
"It appears that Upper Paleolithic people barely used the interior of deep caves for daily, domestic activities. Such activities were mostly performed at open-air sites, rock shelters, or cave entrances," the study says, according to CNN.
"While depictions were not created solely in the deep and dark parts of the caves, images at such locations are a very impressive aspect of cave depictions and are thus the focus of this study," it adds.
According to Ran Barkai, the co-author of the study, the cavemen used fire to light up the caves, which would simultaneously also reduce oxygen levels. Painting in these conditions was done deliberately and as a means of connecting to the cosmos, the researcher says.
"It was used to get connected with things," Barkai told CNN, adding that cave painters often thought of the rock face as a portal connecting their world with the underworld, which was associated with prosperity and growth. The researcher also suggested that cave paintings could have been used as part of a kind of initiation rite.
The fascinating cave paintings, which date from around 40,000 to 14,000 years ago, depict animals such as mammoths, bison, and ibex.
"It was not the decoration that rendered the caves significant but the opposite: The significance of the chosen caves was the reason for their decoration," the study reads, according to CNN.
The study focused on decorated caves in Europe, mostly in Spain and France. It was published last week in the scientific journal "Time and Mind: The Journal of Archaeology, Consciousness, and Culture."
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