From shock to the diencephalon: ECT inventor Ugo Cerletti’s theory of consciousness

This article uncovers an overlooked aspect of Ugo Cerletti’s intellectual journey, highlighting how his work on mental illness, electroconvulsive therapy (ECT), and acroagonines reflected a broader and profound interest in the nature of consciousness. Starting with practical therapeutic innovations, Cerletti ventured into theoretical domains that were both original and pioneering. Understanding epileptic seizures as instances of loss of consciousness, Cerletti proposed that consciousness, primarily associated with sensation—including vigilance, emotion, and memory—arises not from a singular, isolated brain region but through complex interactions among various structures within the diencephalon. In doing so, he challenged several ideas of his time. He criticized the absence of unconscious psychism in the perspectives of Emil Kraepelin and Walter O. Jahrreiss. More remarkably, he opposed the prevailing views of his time, including John Hughlings Jackson’s belief that the cortex was the brain’s superior region responsible for rationality and consciousness. Cerletti sought to disprove this model through evidence drawn from neurological observations, ECT experiments, and contemporary insights from sleep medicine. Moreover, he rejected the dichotomy between rational and emotional brain functions, emphasizing the deeply interconnected nature of these processes.