And they were looking for their own hypoxia to work in trance, because the body releases dopamine in this situation. The situation of the paintings has been analysed and it has been concluded that they were carried out in deep and narrow rooms and galleries of the caves, i.e. in areas with low oxygen content, with an atmospheric concentration of 21% and a fall of up to 11% in some of the positions of the paintings.
In addition, the torches they used to illuminate absorbed oxygen, further decreasing the concentration and increasing the risk of hypoxia, or in this case the possibility.