There's a new twist in the age-old argument over whether cats are smarter than dogs, or vice versa.
The cells are associated with thinking, planning and behaviour, and Herculano-Houzel developed the method for accurately measuring their numbers.
The study was conducted by researchers from six universities in the US, Brazil, Denmark and South Africa.
What the researchers did is take brain matter and essentially turn it into soup. For comparison, in humans, cortical neurons, about 16 billion.
The researchers discovered that dogs have 530 million neurons in their cerebral cortex, while cats have only around 250 million.
For the first time, scientists at Vanderbilt University counted the number of cortical neurons in the brains of both cats and dogs, and found that dogs have almost twice the amount of neurons compared to cats, ABC News reports. Two brains were used to study dogs because the canines vary so greatly in size.
And just to make the cat lovers a little happier, our feline friends have about the same number of neurons as brown bears despite having brains 10 times smaller.
When they looked at a 64-pound golden retriever, the count was even higher: 627 million neurons.
It's always been an epic debate between dog and cat owners, but it seems there is a clear victor.
Of course, such an arbitrary measurement of the brain is not an objective metric of such a complex trait as intelligence.
Until recently, scientists interested in comparing intelligence across species were limited to using brain size as an indicator.
Researchers at Vanderbilt made a decision to put the age old debate to the test objectively, studying the number of cortical neurons in the brains of a number of animals.
The research was done in the lab of Suzana Herculano-Houzel, an associate professor of psychology and biological sciences at Vanderbilt University.
"It's not a larger body that explains the number of neurons you have", she said.
Lead Image: Brewster, the akita/pitbull mix, smiles for the camera.