Ketamine, a drug that induces temporary psychosis-like symptoms, increased the sense of agency in healthy adults, mimicking the exaggerated action-effect binding seen in schizophrenia. In a small experiment, 14 participants given low-dose ketamine showed greater compression of time between their actions and outcomes compared to placebo. The size of this effect correlated with unusual bodily experiences caused by the drug. The findings suggest ketamine can reproduce certain agency disturbances characteristic of schizophrenia, and that these changes are linked to broader alterations in body awareness.
Consciousness, as defined by Julian Jaynes, centers on volition—the experience of willing or choosing. Jaynes argued that consciousness emerged recently in human history, between the writing of the Iliad and the Odyssey. This article highlights the overlooked role of volition in Jaynes' theory, noting that for Jaynes, changes in volitional experience mark the emergence of consciousness. The author draws attention to the fact that volition is central to Jaynes' definition of consciousness, a point not widely noted in critiques of his work.