The psychedelics LSD and ketamine work differently but induce some of the same trippy effects. A new study in rats hints at why: Both drugs trigger the same, simultaneous"wave" of electrical activity across different regions of the brain.
"It seems to be this distinctive wave phenomenon — how the neurons behave collectively — that is most strongly linked to the psychedelic experience," lead study author Pär Halje, a researcher in neurophysiology at Lund University in Sweden, said in a statement. Meanwhile, if you zoom in closer, the activity of individual brain cells looks quite different under the influence of ketamine or LSD, he said.
Both classes of drug altered the activity of two types of cell: interneurons, which connect nerve cells, and excitatory cells known as pyramidal cells. However, while LSD turned down the activity of both of these cell types, ketamine turned down only pyramidal cells and actually turned up interneurons.