What is altered in an altered state of consciousness?

There are currently roughly 100 new scientific papers published on psychedelics and other altered states of consciousness each week. There is broad agreement that these kinds of interventions can have considerable positive impacts on a broad range of mental and physical health conditions. And so a lot of these papers are focused on exploring these clinical outcomes – for example we see many graphs showing that levels of depression and anxiety drop after psychedelic assisted psychotherapy. However, across this booming scientific literature, there is surprisingly little information about what actually happens to participants’ state of consciousness during these interventions.

In my work with the Altered States Lab at Macquarie University we are particularly interested in the measurement and exploration of consciousness change. In this talk I will unpack the different approaches that can be used for scientific measurement of conscious states. I’ll review and critique various contemporary approaches which frame consciousness change as either boundary diffusion, mystical experience, emotional breakthrough, or ego dissolution. I’ll try to highlight the importance and richness of first person experience by sharing data from our lab tracking participants’ subjective experiences during psychedelic, meditation, hypnosis, breathwork, and flicker light interventions. Finally, I’ll propose two new measurement approaches, which aim to capture aspects of altered state experience that have so far been understudied: behavioural indicators of altered consciousness, and the narrative content of participant experiences.