You Don't Think in Words. MIT Just Proved It.

About this work

MIT neuroscientist Evelina Fedorenko's lab tested a question everyone assumes they already know the answer to: does logical reasoning actually require language? They studied people with severe aphasia — a condition, usually from stroke, that strips away the ability to produce or understand speech. If language were the substrate of thought, these are exactly the people who should struggle with logic. They didn't. Participants solved pattern-recognition and syllogism tasks as well as anyone with intact language, some working the problems out through gesture instead of words. The team confirmed it from the other direction too, scanning people with fully intact language during logic tasks — the brain's language network stayed quiet, while a separate "multiple demand" network, tied to general problem-solving, lit up instead. The article breaks down what this means for the inner monologue everyone assumes is "how they think," traces the idea back through a century of philosophy and linguistics that got there first without a scanner, and lays out exactly where this finding does and doesn't apply — including why it says nothing about withholding language from children. Source: Fedorenko, E. et al., PNAS, MIT Department of Brain and Cognitive Sciences, July 2026.