Scientists claim to have found the first evidence that psychedelic drugs create a “higher level of consciousness”.

LSD, the "date rape" drug ketamine and psilocybin, the active ingredient of magic mushrooms, were all found to increase the tiny magnetic fields produced by the brain.

This is used to create a mathematical measure of the complexity of brain activity, with people who are asleep having a lower level than people who are awake.

However the scientists stressed the higher levels seen in people on the psychedelic drugs did not actually equate to something that was "better".

Professor Anil Seth, co-director of the Sackler Centre for Consciousness Science at Sussex University, said: “This finding shows that the brain-on-psychedelics behaves very differently from normal.

“During the psychedelic state, the electrical activity of the brain is less predictable and less ‘integrated’ than during normal conscious wakefulness – as measured by ‘global signal diversity’.

“Since this measure has already shown its value as a measure of ‘conscious level’, we can say that the psychedelic state appears as a higher ‘level’ of consciousness than normal – but only with respect to this specific mathematical measure.”

‘This is your brain on drugs’ advert from the 1980s does more harm than good

It is hoped the findings of the study could help with the development of new treatments for severe depression and other mental conditions using psychedelic substances.

Dr Robin Carhart-Harris, of Imperial College London, said: “Rigorous research into psychedelics is gaining increasing attention, not least because of the therapeutic potential that these drugs may have when used sensibly and under medical supervision.

“The present study's findings help us understand what happens in people’s brains when they experience an expansion of their consciousness under psychedelics.

A trip through time: The history of LSD Show all 5 1 /5 A trip through time: The history of LSD A trip through time: The history of LSD 19 April 1943 Having accidentally ingested LSD three days earlier, Albert Hofmann takes the world's first intentional acid trip and rides home from the lab on his bike. The event is commemorated annually on "Bicycle Day" AFP/Getty Images A trip through time: The history of LSD May 1950 The first article about LSD appears in the American Journal of Psychiatry A trip through time: The history of LSD 22 November 1963 Aldous Huxley, author of The Doors of Perception, instructs his wife to administer him with LSD on his deathbed, and passes away "very, very gently" AP A trip through time: The history of LSD April 1965 The Beatles are introduced to acid by George's dentist. Sgt. Pepper's Lonely Hearts Club Band comes out in June 1967, and while John denies "Lucy in the Sky with Diamonds" was an intentional expansion of "LSD", few believe him Rex Features A trip through time: The history of LSD 14 January 1967 Four years after he is sacked from the psychology department at Harvard, acid evangelist Dr Timothy Leary tells a 30,000-strong gathering at the Human Be-In in San Francisco to, "Turn on, tune in, drop out" Getty Images

“People often say they experience insight under these drugs – and when this occurs in a therapeutic context, it can predict positive outcomes.

“The present findings may help us understand how this can happen.”