To explore the evolution of our understanding of consciousness with a particular emphasis on how corpus callosotomy (split-brain surgery) informed this understanding.

From ancient metaphysical and philosophical hypotheses to contemporary research based on rigorous scientific inquiry, consciousness has long captivated scientists, philosophers, and artists alike. Exploring the origins and tracing the progression of this collective intrigue then, is not merely an intellectual exercise but an attempt to understand the complexities of human perception and unravel the very nature of reality itself.

A scoping review of historical and contemporary literature was conducted, utilizing academic literature from relevant databases and supplementary philosophical texts to ensure a comprehensive historical perspective on consciousness. Selection criteria included peer-reviewed articles and foundational philosophical and neurobiological literature.

The understanding of consciousness has significantly evolved from the metaphysical hypotheses proposed by Plato and Aristotle and since the philosophical approach proposed in Descartes’ Dualism theory. Albeit the empirical contributions of Locke and Gall as well as Penfield’s work in cortical mapping represent critical moments, the most profound insights stem from the visionary research of Roger Sperry and Michael Gazzaniga on hemispherical lateralization and dual consciousness. Their observations on the emergence of two independent streams of consciousness—each with unique awareness and often in direct conflict with the other in post-corpus callosotomy patients—revolutionized existing ideas about consciousness. These works underscoring the modular nature of the brain were pivotal in establishing the foundations for contemporary work on neural network integration.

Although consciousness has long been a fascinating concept inviting perpetual metaphysical and philosophical inquiry into its origins, modern scientific approaches that delve deeper into its neural correlates build upon the insights gained from research on split-brain surgery. This research has been crucial in transforming our understanding of consciousness, grounding it in more rigorous scientific inquiry.