"Seeing Rain": Integrating phenomenological and Bayesian predictive coding approaches to visual hallucinations and self-disturbances (Ichstörungen) in schizophrenia.
Consciousness and Cognition August 1, 2019 Jakob Kaminski, Philipp Sterzer, A. Mishara
A schizophrenia patient who reported 'seeing rain' along with bodily sensations that isolated him from his surroundings is examined to understand how visual and multimodal hallucinations contribute to self-disturbances (Ichstörungen). Self-disturbances, as described by the early Heidelberg School, involve the self experiencing its own automatic mental processes as alien (a split-off 'doubled-I') or, in 'I-paralysis,' attributing disruptions to external omnipotent agents. These disturbances reflect an impaired ability to predict moment-to-moment experiences in the perception-action cycle. The phenomenological analysis complements computational models of psychosis based on hierarchical predictive coding. Self-disturbances appear to play an adaptive, compensatory role following the uncoupling of perception and action.