What Did They Find in Einstein's Brain — And Does It Show Anything About His Intelligence?

When Albert Einstein died in Princeton in April 1955, the pathologist who performed his autopsy did something Einstein had explicitly not consented to: he removed the brain and kept it. Thomas Harvey, the pathologist, believed he was preserving something of scientific value. What followed was one of the stranger episodes in the history of neuroscience — decades of a brain in jars, distributed in sections to researchers around the world, generating a series of studies that are fascinating, contested, and ultimately more revealing about the limits of neuroscience than about the origins of genius.

The question at the heart of all this research is one that connects directly to what we know about what distinguishes exceptional minds — and whether that distinction is visible in the brain's physical structure. Einstein's case is the most famous attempt to answer that question from the outside in.

The Brain's Strange Journey

Harvey photographed Einstein's brain extensively before sectioning it into approximately 240 blocks, which he distributed to researchers over the following decades. The brain traveled with Harvey across the United States for years, residing at various points in cardboard boxes and mason jars. Harvey was not a brain researcher, and he had no institutional framework for managing what he had taken. It was not until the 1980s that the first peer-reviewed research emerged, and not until the 1990s that the most widely cited findings were published.

One immediate finding was that Einstein's brain was not remarkable in overall size. At approximately 1,230 grams, it fell at the low end of average for an adult male — a direct challenge to the folk intuition that bigger brains mean smarter people. Whatever made Einstein's cognition exceptional, it was not simply a matter of having more brain.

What Witelson Found: The Parietal Lobe Difference

The most influential study of Einstein's brain was published in 1999 by neurobiologist Sandra Witelson and colleagues at McMaster University, in The Lancet. Working from Harvey's original photographs of the intact brain, Witelson's team found two notable anatomical differences in Einstein's parietal lobes — regions associated with visuospatial cognition, mathematical reasoning, and the integration of sensory information.

First, Einstein's parietal lobes were approximately 15% wider than those of a comparison group of 35 male brains. This expansion was bilateral — present on both sides — and concentrated in the inferior parietal lobule, a region that processes spatial relationships, numerical reasoning, and the kind of imagery-based thinking Einstein himself described using when developing his theories. Einstein famously reported that he thought in images and physical sensations rather than words, and the parietal cortex is central to exactly this kind of visuospatial mental simulation.

Second, Witelson found that Einstein's Sylvian fissure — a major groove separating the temporal lobe from the parietal and frontal lobes — followed an unusual trajectory. In most brains, this fissure curves upward and divides a region called the supramarginal gyrus. In Einstein's brain, the fissure took a different path that left the supramarginal gyrus unusually intact and undivided. Witelson proposed that this anatomical quirk may have allowed neurons in the parietal region to form more extensive connections with each other, potentially supporting the kind of integrated, imagery-based reasoning that characterized Einstein's thinking.

What Falk Found: The Prefrontal Cortex

In 2012, evolutionary anthropologist Dean Falk and colleagues published a more comprehensive analysis in the journal Brain, working from 14 previously unpublished photographs of Einstein's brain that came to light when Harvey's estate transferred materials to the National Museum of Health and Medicine. Falk's analysis confirmed the enlarged parietal regions found by Witelson and identified additional features — including an unusually complex and highly folded prefrontal cortex, and expanded regions in the primary somatosensory and motor cortices of the left hemisphere corresponding to the face and hands.

The expanded hand and face representations are intriguing. Einstein was a serious and accomplished violinist throughout his life, and the motor and somatosensory regions corresponding to the hands are known to expand with years of instrument practice — a structural example of neuroplasticity driven by sustained use. Whether this expansion preceded or resulted from decades of violin playing cannot be determined from a post-mortem brain, but it illustrates the fundamental interpretive problem with all of this research.

What These Findings Cannot Tell Us

Every study of Einstein's brain faces the same insurmountable limitation: it is a sample of one, examined after death, without any baseline measurement from before he became exceptional, without any ability to compare to the brains of other people of comparable intellectual achievement, and without any way to distinguish cause from effect.

The enlarged parietal lobes might have facilitated visuospatial reasoning that enabled Einstein's physics. Or they might have grown in response to decades of intensive visuospatial thinking — a consequence rather than a cause. Or they might be an anatomical coincidence unrelated to his intellectual capacities. A single brain cannot adjudicate between these possibilities.

The broader problem is one of comparison. To claim that a specific anatomical feature explains genius, you would need to show that the feature is consistently present in people of comparable intellectual achievement and consistently absent in those of average ability. Einstein's brain is a single data point, and one that was handled in non-ideal conditions for decades before systematic study began. The photographs that formed the basis of most research were taken in 1955 with the technology of that era, and the brain itself was fixed and sectioned in ways that make precise measurement difficult.

There is also a publication bias problem. The studies that found interesting features of Einstein's brain were published; the null findings — the many ways in which Einstein's brain was entirely typical — received less attention. The overall picture of a brain with a few notable departures from the norm and many ordinary features is less exciting than the narrative of a fundamentally different brain, but it is closer to what the evidence actually shows.

What the Research Does Suggest

Despite its limitations, the Einstein brain research is not without value. It is consistent with — though far from proving — a model of exceptional visuospatial and mathematical cognition that depends on the parietal cortex. The parietal regions implicated in Einstein's unusual anatomy are the same regions that modern neuroimaging identifies as central to mathematical reasoning, spatial manipulation, and the kind of relational thinking that theoretical physics demands. The correspondence is suggestive even if it is not conclusive.

The research also illustrates something important about the relationship between brain structure and cognitive ability more generally: the differences that matter are likely to be subtle, localized, and context-dependent rather than global. Einstein's brain was not simply a bigger or better version of an average brain. It had specific regions that were enlarged or structured differently, in ways that may have been functionally relevant to his particular cognitive strengths — which were themselves quite specific. Einstein was not universally exceptional; he was extraordinarily capable at a particular kind of physics thinking that relied heavily on visuospatial mental simulation.

This fits with what cognitive science more broadly suggests about exceptional performance — that it is domain-specific, built on specific cognitive strengths rather than generic superiority, and likely involves a combination of unusual neural architecture and decades of deliberate, focused practice in a specific domain. The research on what distinguishes exceptional minds consistently points to working memory, pattern recognition, and domain-specific expertise rather than any single structural feature.

The Bigger Picture

Einstein's brain has become something of a cultural object — a relic that people want to explain genius rather than a scientific specimen that can actually do so. The neuroscience that has emerged from studying it is genuinely interesting, but it is preliminary, contested, and limited by the nature of the evidence. What a single post-mortem brain can tell us about the neural basis of one person's exceptional thinking is inherently constrained.

What the research does contribute is a set of hypotheses about the neural correlates of visuospatial and mathematical cognition that can be — and are being — tested with modern neuroimaging in living participants. The parietal lobe findings from Einstein's brain helped motivate research into the neural basis of spatial and mathematical reasoning that has produced far more rigorous and generalizable insights than the original case study could provide.

The more productive question is not "what made Einstein's brain special?" but "what cognitive capacities underlie exceptional mathematical and scientific thinking, and how do they develop?" That question is being answered — incrementally, with appropriate scientific caution — by research on working memory, fluid intelligence, pattern recognition, and the neural systems that support them. The Matrix Reasoning test and N-Back test directly engage the visuospatial and working memory systems that Einstein's parietal research points toward — measuring the living cognitive capacities that a post-mortem brain can only hint at.