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Suzana Herculano-Houzel - Vanderbilt University. Nashville, TN, US

Suzana Herculano-Houzel Suzana Herculano-Houzel

Associate Professor of Psychology | Vanderbilt University


Neuroscientist and international expert in how brain size and structure affect cognition and longevity in animals.





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Watch: Study gives new meaning to the term “bird brain” Watch: The Human Advantage: A New Understanding of How Our Brain Became Remarkable Watch: Sorry Grumpy Cat, study finds dogs are brainier than cats TED Talk: What is so special about the human brain?



Suzana Herculano-Houzel, P.I. (her.kou.LAH.no.who.ZELL) is Associate Professor of the Departments of Psychology and Biological Sciences at Vanderbilt University since 2016. She was previously an Associate Professor at Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil, between 2002-2016.

She majored in Biology at Universidade Federal do Rio de Janeiro (1992), holds an M.Sc. in Neuroscience (Case Western Reserve University, 1995, with Story Landis), and a Ph.D. in Neuroscience (Université Paris VI, 1999, with Yves Frégnac and Max-Planck-Institut for Brain Research, with Wolf Singer). In Brazil, she was a Scientist with the National Research Council (CNPq) from 2007 to 2016; Young Scientist of the State of Rio de Janeiro (FAPERJ, 2007-2009) and Scientist of the State of Rio de Janeiro (FAPERJ) between 2009 and 2016. In 2010, she was a recipient of the Scholar Award in Understanding Human Cognition, James S. McDonell Foundation.

She is the author of six books (in Portuguese) for the general public on the neuroscience of everyday life, with over 80,000 copies sold, was the writer and presenter of the TV series Neurológica (Fantástico, Rede Globo de Televisão) between 2008 and 2011, and remains a regular writer for the newspaper Folha de São Paulo since 2006.

Areas of Expertise (8)



Cognition and Cognitive Neuroscience



Developmental Science

Quantitative Methods

Animal intelligence

Accomplishments (6)

Fall 2019 Public Voices Fellow (professional)

A semester-long program designed to expand Vanderbilt University’s global reach by amplifying the impact of faculty academic research.

LARC-IBRO Travel Award, FALAN (professional)


Scholar Award in Understanding Human Cognition, James McDonnell Foundation (professional)


Carioca of the Year Award (Scientist – Veja magazine) (professional)


Personalities of the Year (Scientist – Época magazine) (professional)


Creative Women Award (Sciences – Criativa magazine) (professional)


Education (3)

Université Pierre: Ph.D., Neuroscience 1999

Case Western Reserve University: M.Sc., Neuroscience 1995

Universidade Federal do Rio de Janeiro: B.Sc., Biology/Genetics 1992

Selected Media Appearances (4)

How pieces of live human brain are helping scientists map nerve cells

ScienceNews  online


These similarities don’t surprise Suzana Herculano-Houzel, a neurobiologist at Vanderbilt University in Nashville. “We are not special,” she says. Finding that humans and mice have similar types of cells in their brains makes a lot of sense, as does the idea that some cell types and some genes will be species-specific. The question is, she says: “Which of those differences are actually meaningful?”

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Lifespan and sexual maturity depends on your brain more than your body

ScienceDaily  online


"Whether you're looking at birds or primates or humans, the number of neurons that you find in the cortex of a species predicts around 75 percent of all of the variation in longevity across species," said study author associate professor of psychology and biological sciences Suzana Herculano-Houzel.

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Dogs versus cats: Scientists reveal which one is smarter

Fox News  online


“I believe the absolute number of neurons an animal has, especially in the cerebral cortex, determines the richness of their internal mental state and their ability to predict what is about to happen in their environment based on past experience,” neuroscientist Suzana Herculano-Houzel from Vanderbilt University says.

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Suzana Herculano-Houzel

New York Times  online


In the early years of Herculano-Houzel’s research, especially once she graduated from rats to primates, she encountered substantial resistance from her peers. Here was a young, essentially unknown scientist from Brazil not only proposing a radically different way of studying the brain but also contradicting centuries of conventional wisdom. “At first I shared the same opinion as everyone else,” says Andrew Iwaniuk, an evolutionary neuroscientist at the University of Lethbridge in Alberta, Canada. “This is insane. This can’t possibly work. What do you mean you are blending an entire brain and coming up with the number of neurons?”

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Selected Articles (3)

Embodied (embrained?) cognitive evolution, at last! Comparative Cognition & Behavior Reviews

Suzana Herculano-Houzel

2018 It is time that brain size stops serving as a black box-type property of brains, "somehow" related to variations in cognitive performance across species. We now know that hidden behind similar brain structure sizes are diverse numbers of neurons and fibers that can differ in function according to experience and environment and that species differences are not a continuation of individual differences.

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Longevity and sexual maturity vary across species with number of cortical neurons, and humans are no exception The Journal of Comparative Neurology

Suzana Herculano-Houzel

2018 Maximal longevity of endotherms has long been considered to increase with decreasing specific metabolic rate, and thus with increasing body mass. Using a dataset of over 700 species, here I show that maximal longevity, age at sexual maturity and post‐maturity longevity across bird and mammalian species instead correlate primarily, and universally, with the number of cortical brain neurons.

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You Do Not Mess with the Glia Neuroglia

Suzana Herculano-Houzel, Sandra Dos Santos

2018 Vertebrate neurons are enormously variable in morphology and distribution. While different glial cell types do exist, they are much less diverse than neurons. Over the last decade, we have conducted quantitative studies of the absolute numbers, densities, and proportions at which non-neuronal cells occur in relation to neurons.

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