Immersive exposure to simulated visual hallucinations modulates high-level human cognition.

Psychedelic drugs offer valuable insights into consciousness, but disentangling their causal effects on perceptual and high-level cognition is nontrivial. Technological advances in virtual reality (VR) and machine learning have enabled the immersive simulation of visual hallucinations. However, comprehensive experimental data on how these simulated hallucinations affects high-level human cognition is lacking. Here, we exposed human participants to VR panoramic videos and their psychedelic counterparts generated by the DeepDream algorithm. Participants exhibited reduced task-switching costs after simulated psychedelic exposure compared to naturalistic exposure, consistent with increased cognitive flexibility. No significant differences were observed between naturalistic and simulated psychedelic exposure in linguistic automatic association tasks at word and sentence levels. Crucially, visually grounded high-level cognitive processes were modulated by exposure to simulated hallucinations. Our results provide insights into the interdependence of bottom-up and top-down cognitive processes and altered states of consciousness without pharmacological intervention, potentially informing both basic neuroscience and clinical applications.