Problem This Solves
Popular accounts treat the hemispheres as handling different tasks (language vs. spatial reasoning, logic vs. creativity). This misses the real distinction. McGilchrist systematically demonstrates that the hemispheres differ not in what they do but in how they attend to the world, constituting two fundamentally different orientations toward reality.
Key Principle
The two hemispheres embody two ways of being in the world. The left hemisphere offers narrow focused attention, abstraction from context, categorisation, re-presentation, manipulation, certainty, and positive feedback. The right hemisphere offers broad vigilant attention, contextual understanding, recognition of individuals, direct presence, empathy, tolerance of ambiguity, and negative feedback (self-correction). Neither is sufficient alone; the problem arises from imbalance.
Good Examples
- Attention: The right hemisphere is responsible for every type of attention except focused attention. "Global attention, courtesy of the right hemisphere, comes first, not just in time, but takes precedence in our sense of what it is we are attending to."
- Context vs. abstraction: The left hemisphere understands "'it's a bit hot in here today'" as meteorological data; the right hemisphere understands it as "'please open a window.'"
- Individuals vs. categories: The right hemisphere recognises unique individuals; the left classifies by abstract categories. "Individuals are, after all, Gestalt wholes: that face, that voice, that gait, that sheer 'quiddity' of the person or thing, defying analysis into parts."
- The new vs. the known: Learning a musical instrument initially engages the right hemisphere, then shifts to the left as mastery develops. But Bach's contrapuntal music re-engages the right hemisphere because it resists routine.
- The living vs. the non-living: "It is the left hemisphere alone that codes for non-living things," while both hemispheres code for living things.
- Empathy: Mirror neurons exist in both hemispheres, but empathic, social imitation depends on the right hemisphere. The right hemisphere will empathise only with what it knows to be a living being, not a mechanism.
Bad Examples
- Confabulation: The left hemisphere fabricates plausible explanations rather than admit ignorance -- "the equivalent of the sort of person who, when asked for directions, prefers to make something up rather than admit to not knowing."
- Hemi-neglect: Right-hemisphere stroke causes neglect of the left half of space, body, and world; left-hemisphere stroke does not produce the mirror image, because the right hemisphere alone delivers a complete world.
- Capgras syndrome: A right-hemisphere deficit causes a patient to believe a loved one has been replaced by an impostor -- small perceptual changes are no longer integrated into a unified whole.
- Denial of the body: Patients with right-hemisphere damage deny ownership of their left limbs, claim they belong to someone else, or describe them as made of plastic. One patient insisted her paralysed arm belonged to her mother.
- Loss of social capacity: Without the right hemisphere, "social intercourse is conducted with a blanket disregard for the feelings, wishes, needs and expectations of others."
Key Quotes
"The left hemisphere can only re-present; but the right hemisphere, for its part, can only give again what 'presences'. This is close to the core of what differentiates the hemispheres."
"Without batting an eye the left hemisphere draws mistaken conclusions from the information available to it and lays down the law about what only the right hemisphere can know."
"Social intercourse is conducted with a blanket disregard for the feelings, wishes, needs and expectations of others."
"Whatever the relationship between consciousness and the brain -- unless the brain plays no role in bringing the world as we experience it into being, a position that must have few adherents -- its structure has to be significant."
Rules of Thumb
- Re-presentation vs. presence is "close to the core" of the distinction. Recognise when you are operating on a model of reality rather than reality itself.
- The right hemisphere operates like a self-correcting system (negative feedback), while the left tends toward positive feedback loops. "This is not unlike the difference between the normal drinker and the addict."
- Narrow, focused attention (left) and broad, vigilant attention (right) are both necessary but serve different purposes. Cultivate awareness of which mode you are operating in.
- Expertise and familiarity shift processing leftward, potentially reducing openness to anomalies. Deliberately seek fresh perspectives on familiar problems.
- Be suspicious of overly neat explanations, especially when they come with great confidence -- this is the left hemisphere's confabulation tendency at work.
- The right hemisphere experiences the body as lived (Leib); the left treats it as a thing (Korper). Notice when your thinking treats living, dynamic realities as static, mechanical objects.
Related References
- [[core-framework]] -- The overarching thesis and the right-left-right cycle
- [[attention-and-reality]] -- How attention constitutes reality
- [[language-metaphor-music]] -- Language and metaphor as hemisphere-differentiated capacities