The term 'left brain', as conceived by Iain McGilchrist, refers to the hemisphere of the brain that processes information in an analytic, linear, and sequential manner. It emphasizes language, logic, and mathematics, often breaking down complex phenomena into constituent parts for examination. This hemisphere excels at abstraction, dealing with known and familiar concepts where rules and predictability dominate. Fundamentally, the left brain is characterized by a mode of attention that is narrow, focused, and detail-oriented, facilitating the manipulation and categorization of the external world, typically at the expense of context and holistic understanding. While its capabilities are essential for certain tasks, it must be balanced with the right hemisphere to fully engage with the richness and complexity of reality.

See also: left hemisphere, right hemisphere, corpus callosum, split brain, hemispheric hypothesis